The total amount of infection needed to develop symptoms of measles is 7840
Consider the model,
N(t)= f(t)=-t(t-21)(t+1).
The area of the graph of N(t) from t=0 to t = 12 is,
N(t)dt
Use six subintervals and their midpoints to estimate the above as follows:
Here, a=0,b=12, n=6
The length of each subinterval is,
h= b-a/n = 12-0/6
=2
So, the midpoints of each subinterval are 1, 3, 5, 7, 9, and 11.
Use Midpoint Rule,
A = [N(t)dt]
= At[ƒ (1) + ƒ (3) + ƒ (5) +ƒ(7)+ƒ(9)+ƒ(11)] =2[40+216+480+784+1080+1320]
= 7840
Thus, the total amount of infection needed to develop symptoms of measles is 7840.
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in a family with 7 children, excluding multiple births, what is the probability of having 3 boys and 4 girls
The probability having of 3 boys and 4 girls is 33 or 0.33
what is probability?
The area of mathematics known as probability deals with numerical descriptions of how likely it is for an event to happen or for a proposition to be true. A number between 0 and 1 is the probability of an event, where, roughly speaking, 0 denotes the event's impossibility and 1 denotes its certainty.
solution:
Assuming 50/50 chance on boy/girl we see following outcome:
(1/2^7).
Since there is only one way you can have 3 girls, followed by 4 boys.
If you would tell the boys apart, and the girls, for instance by their names, the probability would be:
6 * (1/2)^3 *(1/2)^4 * 24.
6 Times because the girls would then have 6 orders of having been born.
24 Times because then the boys would have 24 orders of having been born.
Therefore, The probability of 3 boys and 4 girls is 33 or 0.33
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Shera is building a cabinet. She is making wooden braces for the corners of the cabinet. Find the surface area of each brace.
The surface area of each brace of the cabinet is 30 square inches
What is the surface area of each brace?length = 3 inWidth = 3 inHeight = 1 inSurface area of the first brace = 2 (lh +wh + lw )
= 2{(3×1) + (3 × 1) + (3 × 3)}
= 2(3 + 3 + 9)
= 2(15)
= 30 square inches
Surface area of the second brace = 2 (lh +wh + lw)
= 2{(3×1) + (3 × 1) + (3 × 3)}
= 2(3 + 3 + 9)
= 2(15)
= 30 square inches
Total surface area of the cabinet = Surface area of the first brace + Surface area of the second brace
= 30 square inches + 30 square inches
= 60 square inches
Consequently, the total surface area of the cabinet is 60 square inches
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A directional hypothesisrequires a paired t-test.tests whether error variance is smaller or larger than systematic variance.stipulates whether alpha or beta is most important.predicts which of two means will be larger.
Answer:D
Step-by-step explanation:D
A charity bingo game costs $2 per round and has a $13 entry fee for an adult. It costs $3 per round and a $10 entry fee for a child. For how many rounds of bingo are the costs the same for an adult and a child?
2
3
4
5
Answer:
it is 5 you don't add the 3 in it
license plates in a country far away consist of 2 letters followed by 4 digits (0-9). if the only restriction is that plates can not have the same digit 4 consecutive times, how many plates are possible? (so sw-4444) is not allowed by (sw-4443) is
As per the given probability, there are 6760000 number of plates number are possible.
Probability:
In math, probability means the possibility of favorable outcome.
Given,
License plates in a country far away consist of 2 letters followed by 4 digits (0-9). if the only restriction is that plates can not have the same digit 4 consecutive times,
Here we need to find how many plates are possible.
Here we have given that, A license plate composed of 2 letters followed by 4 digits.
The first step is considering the letters in the plate.
Here we know that, the plate consists of 2 letters.
And in alphabets, we have 26 letters which start from A to Z.
Therefore, we can choose 2 letters from 26 letters in 26² ways.
Now, we considering the digits in the plate.
Here the plate consists of 4 digits.
And we have 10 digits which starts from 0 to 9.
Now we can choose 4 digits from 10 digits in 10⁴ ways.
Therefore, the number of possible plates is
=> 26² × 10⁴
=> 676 x 10000
=> 6760000
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PLEASE HELP WITH THIS PICTURE IM STUCK
Answer:
A. The plane will travel 1180 miles in 10 hours
B. The plane is traveling at a rate of 118 miles per hour
Step-by-step explanation:
Step 1: Divide 590 by 5 to get how many miles it travels in 1 hour
1. 590/5 = 118 miles per hour
Step 2: Multiply 118 by 10 to get how many miles it travels in 10 hours
2. 118 ∙ 10 = 1180 miles per 10 hours
help please might give brainliest answer
FILL IN THE BLANK. Fill in the blank: A data analyst uses _____ to decide which data is relevant to their analysis and which data types and variables are appropriate.
Answer:
statistical methods
Step-by-step explanation:
Data analyst uses to "Database organization" to decide which data is relevant to their analysis and which data types and variables are appropriate.
What is database organization ?A database is a structured information collection that is often kept electronically in a computer system. Typically, a database management system is in charge of managing a database (DBMS).
It is a system, frequently abbreviated to just database, is the collective term for the data, the DBMS, and the applications that are connected to it.
The most popular forms of databases, today usually describe their data in rows and columns in a collection of tables to facilitate processing and data querying.
Also the information may then be accessed, managed, changed, updated, regulated, and organized with ease. SQL is a structured query language that is used by the majority of databases to write and query data.
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thankss tooooo urgenttt tooo
Doug buys a pumpkin every year. The first time he bought a pumpkin, at year 0, it cost $2.60. He notices the price is getting more expensive, at a rate of 7% per year.
Doug sketches a graph of the situation.
Which statements are true?
Select each correct answer.
Responses
The graph has an x-intercept and a y-intercept.
The graph has an , x, -intercept and a , y, -intercept.
The graph increases from left to right.
The graph increases from left to right.
The point (0, 2.60) is on the graph.
The point , , , begin ordered pair 0 comma 2.60 end ordered pair, , , is on the graph.
The graph has a y-intercept only.
The graph has a , y, -intercept only.
The graph decreases from left to right.
The graph decreases from left to right.
The point (2.60, 0) is on the graph.
The correct statements regarding the graph of the exponential function y = 2.60(1.07)^x are given as follows:
The graph increases from left to right.The point (0, 2.60) is on the graph.The graph has a y-intercept only.What is the definition of the exponential function?The definition of an increasing exponential function is given as follows:
y = a(1 + r)^t.
In which the parameters are given as follows:
a is the y-intercept of the exponential function, representing the initial value.r is the growth rate of the exponential function.In the context of this problem, the values of these parameters are given as follows:
a = 2.6, r = 0.07.
Hence the function is given as follows:
y = 2.6(1.07)^x.
The features of the function are given as follows:
y-intercept at point (0, 2.6).Increasing, as the term elevated to x has an absolute value greater than 1.No x-intercepts, as the horizontal asymptote of the graph is at x = 0.More can be learned about exponential functions at https://brainly.com/question/25537936
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WILL GIVE BRAINLEST! AND 20 POINTS!
Answer:
i need the points
Step-by-step explanation:
idek
Answer: Choice B.
The relationship is not proportional. The number of water bottles that are thrown away Increases from month to month than the number of water bottles that are recycled.
probability of rolling a 6 with two dice one with values 1, 2, 2, 3, 3, 4 and 1, 3, 4, 5, 6, 8
Answer:
11/12 chance of the probability of rolling a 6 with 2 dice
the mean water temperature downstream from a discharge pipe at a power plant cooling tower should be no more than 100°f. assume the water temperature is approximately normally distributed with standard deviation of 2°f. the water temperature is measured on nine randomly chosen days, and the sample average of those nine temperatures is found to be 98°f. (a) is there sufficient evidence in the sample data to support the claim that the mean water temperature is not acceptable at α
A) Yes , there is there sufficient evidence in the sample data to support the claim that the mean water temperature is not acceptable at α.
Hypothesis test for the given population mean :
The claim is that the mean water temperature is significantly below 100 °F.
Then, the null and alternative hypothesis are:
H0 : Ц = 100
H1 : Ц < 100
The significance level is 0.05.
The sample has a size n=9.
The sample mean is M=98.
The standard deviation : σ=2
Standard error = 0.667
Z = -3
Therefore, P-value (0.001) is smaller than the significance level (0.05)
The null hypothesis is rejected.
The hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error is known as null hypothesis.
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In parallelogram wxyz, what is cy? 11 ft 15 ft 21 ft 23 ft
The CY in the given Parallelogram WXYZ is 15 ft.
A parallelogram is defined as, "A geometrical figure whose sides are parallel to each other. "
In the given Parallelogram WXYZ, the length of the sides is not given. Although, the length of the two diagonal sides is given which are CY and CW with a variable x. The following are the values of these two diagonals:
CY = (2x - 7) ft .....(1)
CW = (x + 4) ft ......(2)
In this given question, we need to find the value of CY. So, we can find the value of CY by finding the value of variable x.
To find the value of x, we follow the theorem:
"In the parallelogram, The diagonals bisect each other"
We get that,
CY = CW ......(3)
By putting the value equation (1) and (2) in equation (3), we get
2x - 7 = x + 4 ......(1)
By subtracting 'x' and adding '7' on both sides of the equation.
x = 11,
So we get,
x = 11.
By putting the value of 'x' in equation (1), we get:
CY = 2(11) - 7 = 11 - 7
CY = 4.
Hence, the value of CY is 4.
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Choose the expression that is equivalent to 8-^10/(8^4)(8^0)
1/8^14
8^14
- 1/8^14
- 8^14
The expression 1/8¹⁴ is equivalent to 8⁻¹⁰ / (8⁴)(8⁰). The 1st option is the answer
How to determine the expression that is equivalent to 8⁻¹⁰ / (8⁴)(8⁰)?
Index ( plural indices) is the power or exponent which is raised to a number or a variable e.g in number 3⁵, 5 is the index of 3.
Given: the expression 8⁻¹⁰ / (8⁴)(8⁰)
8⁻¹⁰ / (8⁴)(8⁰) can be written as:
8⁻¹⁰ / (8⁴)(8⁰) = 8⁻¹⁰ / (8⁴)(1) (Note: 8⁰ = 1)
= 8⁻¹⁰ / 8⁴ (Note: 1/8⁴ = 8⁻⁴ )
= 8⁻¹⁰ × 8⁻⁴
= 8⁻¹⁰ ⁺ ⁻⁴
= 8⁻¹⁴
= 1/8¹⁴
Thus, 1/8¹⁴ is the equivalent to 8⁻¹⁰ / (8⁴)(8⁰)
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how to evaluate 8.1p plus 7.9r when p=6 and r=7
The value of the expression 8.1p plus 7.9r when p=6 and r=7 will be 103.9.
What is an expression?A mixture of variables, numbers, addition, subtraction, multiplication, and division are called expressions.
A statement expressing the equality of two mathematical expressions is known as an equation.
An expression is a mathematical proof of the equality of two mathematical expressions.
8.1p + 7.9r = 8.1(6) + 7.9(7)
⇒ 103.9
Hence "The value of the expression 8.1p plus 7.9r when p=6 and r=7 will be 103.9".
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problem 4. a player plays a game where she is equally likely to win or lose 1 dollar. the games are independent. the player will continue playing until the first win occurs and then stop immediately after. (a) find the probability that her winnings are greater than zero. (b) find the probability that her winnings are less than zero. (c) find the expected value of her winnings.
We get
(A) The probability that her winnings will exceed zero is 0.50.
(B) The probability that her winnings will be less than zero is 0.25.
(c) Her winnings' estimated worth is 0.
Given that,
A player engages in a game where the odds of winning or losing one dollar are equal. The games are stand-alone. The game will be played until the first win occurs, at which point the player will instantly stop.
We have to find
(A) determine the probability that her winnings will exceed zero.
(B) calculate the probability that her winnings will be less than zero.
(c) calculate her winnings' estimated worth.
We know that,
a) probability that her winnings are greater than zero =P(wins 1st game) =1/2 =
b) probability that her winnings are less than zero =P(lose 1st 2 games) =(1/2)×(1/2 )=1/4 =0.25
c) below is pmf of X (gain from the game)
P(X=1)=P(win 1st game) =1/2
P(X=0)=P(lose 1st and win 2nd) =(1/2)×(1/2) =1/4
P(X=-1)=P(lose 1st two and wins 3rd)=(1/2)×(1/2)×(1/2) =1/8
P(X=-2)=1/16
therefore expected value E(X )=ΣxP(x) =1×1/2+0×1/4-1×1/8-2×1/16........
= (1/2)+0-(1×1/8+2×1/16+3×1/32+4×1/64+...)
=(1/2)-(1/4)×(1/(1/2))
=(1/2)-(1/2)
=0
Therefore,
(A) The probability that her winnings will exceed zero is 0.50.
(B) The probability that her winnings will be less than zero is 0.25.
(c) Her winnings' estimated worth is 0.
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Find:
11/3÷2/3
the question is five and
We keep the first number 11/3, change ÷ to ×, and flip 2/3 to 3/2:
11/3 x 3/2 = 33/6
Simplify:33/6 ÷ 3/3 = 11/2
Solution:11/2I hope my answer helped you! If you need more information or help, comment down below and I will be sure to respond if I am online. Have a wonderful rest of your day!
Find the real solution(s) of the equation. Round your answer to the nearest hundredth. 12x^4 = 78
Answer:
x = 4√104/2
Step-by-step explanation:
Select all of the choices that are equal to (-5)-(-12)
Answer:
7 {No choices are given}
Step-by-step explanation:
Given problem,
→ (-5) - (-12)
Let's solve the problem,
→ (-5) - (-12)
→ (-5) + 12
→ (-5 + 12) = 7
Thus, the answer is 7.
researchers studied the behavior of birds that were searching for seeds and insects in an oregon forest. in this forest, 54% of the trees were douglas firs, 40% were ponderosa pines, and 6% were other types of trees. at a randomly selected time during the day, the researchers observed 156 red-breasted nuthatches: 70 were seen in douglas firs, 79 in ponderosa pines, and 7 in other types of trees. Do these data provide convincing evidence that nuthatches prefer particular types of trees when they're searching for seeds and insects?
Yes, the given data provide convincing evidence that the Nuthatches prefer particular types of trees while searching for seeds and insects.
A statistical hypothesis test used to examine if a variable is likely to come from a given distribution is the Chi-square goodness of fit test. It is frequently used to assess how well sampling data represents the entire population.
Given that the number of red-breasted nuthatches (n) is 156. By convention, the significance level is α=0.05.
First, let's state the null hypothesis and alternate hypothesis.
Null hypothesis H₀: Nuthatches don't prefer particular types of trees while searching for seeds and insects.
Alternate hypothesis H₁: Nuthatches prefer particular types of trees while searching for seeds and insects.
Given: p₁=54%=0.54, p₂=40%=0.40, p₃=6%=0.06
The expected frequency (E) for each probability is:
[tex]\begin{aligned}E_1&=np_{1}\\&=156\times0.54\\&=84.24\\E_2&=np_{2}\\&=156\times0.40\\&=62.4\\E_3&=np_{3}\\&=156\times0.06\\&=9.36\end{aligned}[/tex]
The observed values (O) are given as 70, 79, and 7. Calculating chi-square, we get,
[tex]\begin{aligned}\chi^{2}&=\sum\frac{(O-E)^2}{E}\\&=\frac{(70-84.24)^2}{84.24}+\frac{(79-62.4)^2}{62.4}+\frac{(7-9.36)^2}{9.36}\\&=7.4182\end{aligned}[/tex]
And the degree of freedom is given by df = n-1, where, n is the sample size. Here, the sample size is 3.
[tex]\begin{aligned}df&=n-1\\&=3-1\\&=2\end{aligned}[/tex]
Then, the P-value from the table is given by, [tex]P(\chi^{2} > 7.4182) = 0.0245[/tex].
This value is less than the significance level. Therefore, the null hypothesis is rejected. So, an alternate hypothesis is accepted.
Therefore, nuthatches prefer particular types of trees while searching for seeds and insects.
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A flea weighs 8 decigrams, and an ant weighs 3 milligrams. How much more does a flea weigh than an ant?
milligrams
To compare the weight of a flea and an ant, we first need to convert the weight of the flea and the ant to the same units. Since the weight of the flea is given in decigrams and the weight of the ant is given in milligrams, we can convert the weight of the flea to milligrams by multiplying it by 10.
We can use the following equation to calculate the weight of the flea in milligrams:
weight of flea in milligrams = 8 decigrams * 10 = 80 milligrams
Once we have the weight of the flea and the ant in the same units (milligrams), we can subtract the weight of the ant from the weight of the flea to find the difference in their weights.
We can use the following equation to calculate the difference in weight between the flea and the ant:
difference in weight = weight of flea - weight of ant
difference in weight = 80 milligrams - 3 milligrams
difference in weight = 77 milligrams
Therefore, a flea weighs 77 milligrams more than an ant.
Can 3,8,15 make a triangle
Answer is NO!
hope this helps! Have an amazing and blessed day! :)
Answer: yes
Step-by-step explanation:
The box plots show the math scores of students in two different classes. Based on the box plots, which statement is correct?
A. The median score of Class A is greater than the median score of Class B.
B. The lower quartile of Class A is greater than the lower quartile of Class B.
C. The upper quartile of Class A is greater than the upper quartile of Class B.
D. The maximum score of Class A is greater than the maximum score of Class B.
Based on the box plots, the statement which is correct is that: A. The median score of Class A is greater than the median score of Class B.
What is a box and whisker plot?In Mathematics, a box plot is also referred to as box and whisker plot and it can be defined as a type of chart that can be used to graphically or visually represent the five-number summary of a data set with respect to locality, skewness, and spread.
Additionally, the five-number summary of any box plot (box and whisker plot) include the following:
MinimumFirst quartileMedianThird quartileMaximumBy critically observing the box plot (box and whisker plot) which represent the math scores of students in in two different classes, we can reasonably and logically deduce the following median scores;
Median score of class A = 80
Median score of class B = 75
Therefore, a median score of 80 in Class A is greater than the median score of 75 in Class B.
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Please Help Me. I am stuck on this homework assingment.
The required reasons statements to prove the congruency of the angles the value of x, and the measures of ∠2 and ∠4 are as follows;
Problem 1
The question and the diagram indicates that ∠1 and ∠3 are vertical angles formed by two lines, therefore, ∠1 and ∠3 are both a linear pair and therefore supplementary to ∠2, indicating that m∠1 = m∠3, therefore;
∠1 ≅ ∠3
Problem 2
x = 18°m∠2 = 68°m∠3 = 68°What are supplementary angles?Supplementary angles are angles that have a sum of 180°
The reasons for the statements in the completed table of the two column method used to prove ∠1 ≅ ∠3 are as follows;
Statement [tex]{}[/tex] Reasons
1. ∠1 and ∠3 are vertical angles [tex]{}[/tex] 1. Given
2. ∠1 and ∠2 form a linear pair [tex]{}[/tex] 2. Definition of linear pair
∠2 and ∠3 form a linear pair
3. ∠1 and ∠2 are supplementary [tex]{}[/tex] 3. Linear pair ∠s are supplementary
∠2 and ∠3 are supplementary
4. m∠1 + m∠2 = 180° [tex]{}[/tex] 4. Definition of supplementary ∠s
m∠2 + m∠3 = 180°
5. m∠1 + m∠2 = m∠2 + m∠3 [tex]{}[/tex] 5. Substitution property
6. m∠1 = m∠3 [tex]{}[/tex] 6. Subtraction property
7. ∠1 ≅ ∠3 [tex]{}[/tex] 7. Definition of congruency
Problem 2
∠2 = 4·x - 4
∠4 = x + 50
∠2 and ∠4 are vertical angles, therefore;
∠2 ≅ ∠4 (Vertical angle theorem)
m∠2 = m∠4 (definition of congruency)
4·x - 4 = x + 50 (substitution property)
4·x - x = 4 + 50 = 54
3·x = 54
x = 54 ÷ 3 = 18
x = 18°
m∠2 = (4 × 18 - 4)° = 68°
m∠3 = (18 + 50)° = 68°
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PLEASE ANSWER
ANSWER!!!!!!!
This scatter plot shows the number of magazines checked out and the number of books checked out.
Choose the statement that is best supported by the data in the scatter plot.
The data shows a negative linear association between the number of magazines checked out and the number of books checked out.
The data shows a negative linear association between the number of magazines checked out and the number of books checked out.
The data shows a positive linear association between the number of magazines checked out and the number of books checked out.
The data shows a positive linear association between the number of magazines checked out and the number of books checked out.
The data shows a non-linear association between the number of magazines checked out and the number of books checked out.
The data shows a non-linear association between the number of magazines checked out and the number of books checked out.
The data shows no apparent association between the number of magazines checked out and the number of books checked out.
The data shows a negative linear association between the number of magazines checked out and the number of books checked out.
What is Graph?Graph is a mathematical representation of a network and it describes the relationship between lines and points.
Scatter plots are used to plot data points on a horizontal and a vertical axis in the attempt to show how much one variable is affected by another.
If one variable tends to increase as the other decreases, the association is negative.
By observing the scaterplot we understand that the value is decreasing as the other value is increasing.
Hence, The data shows a negative linear association between the number of magazines checked out and the number of books checked out.
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Please answer the question in the picture
In baseball each time a player attempts to hit the ball it is recorded the ratio of his compared to the total Tems is there a batting average each player on the team wants to have the highest batting average to help their team the most for the season so far Jenna has hit the ball 12 times Outta 15 attempts thought I said the 19 out of 10 times which player has a ratio that means you have a better batting average?
The answer is: A) Tasha, because she has the lowest ratio since 0.75 < 0.8
Explain:
i did the test
Answer:
Step-by-step explanation:the answer is a
Students at a high school are asked to evaluate their experience in the class at the end of each school year. The courses are evaluated on a 1-4 scale - with 4 being the best experience possible. In the History Department, the courses typically are evaluated at 10% 1's, 15% 2's, 34% 3's, and 41% 4's. Mr. Goodman sets a goal to outscore these numbers. At the end of the year he takes a random sample of his evaluations and finds 11 1's, 14 2's, 47 3's, and 53 4's. At the 0.05 level of significance, can Mr. Goodman claim that his evaluations are significantly different than the History Department's?
It cannot be concluded that there is a statistically significant difference between Mr. Goodman’s evaluations and the History Department’s
H₀: There is no difference in Mr. Goodman’s evaluations and the History Department’s
H: there is a significant difference between Mr. Goodman’s evaluations and the History Department’s
Applying chi-square test
relative observed Expected residual Chi-square
1's 0.100 11.000 12.500 -0.42 0.180
2's 0.150 14.000 18.750 -1.10 1.203
3's 0.340 47.000 42.500 0.69 0.476
4's 0.410 53.000 51.250 0.24 0.060
total 1.000 125 125 1.9196
test statistic X²=1.9196
p-value =0.5893
Hence it cannot be concluded that there is a statistically significant difference between Mr. Goodman’s evaluations and the History Department’s as we fail to reject the null hypothesis.
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which answer would make the following a false statement? a function parameter ... a. is visible inside the function in which it is defined b. lives until the end of the function is reached. c. is a local variable d. cannot share a name with a variable outside of the function
The following statements make a false statement.
Given that,
A function argument a exists until the function's end is reached.
A local variable
can only share a name with another variable inside the function and exists only until the function's end.
Answer C : Can not share a name with variable outside a function.
Because the function is considered as a single line of code.
Answer True
They have same presidence but they are evaluated from left to right
Answer D : The calculation totals both positive (Profits) and negative (loss) earnings
Code doesn't check if the number of positive or not before adding
Answer D.
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