which of the following is not true of a good hypothesis? a) it includes a null hypothesis b) it is experimentally testable c) it is phrased as an if, then statement d) it must contradict previous theories e) it could explain an unexpected observation.

Answers

Answer 1

False claims do not have to engage with previous theories in order to be effective. So it must contradict previous theories. So the option d is correct.

A tentative, verifiable explanation for a natural world phenomenon is what is known as a scientific hypothesis. The scientific method's foundational element is it.

It's sometimes referred to as a "informed guess" that was made using past knowledge and observation. Despite the fact that this is true, a hypothesis is a better guess.

Creating a hypothesis calls for active observation and background research, in contrast to making a "informed guess," which implies a random prediction based on one's expertise. A hypothesis is predicated on the fundamental tenet that no outcome is predetermined.

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Related Questions

So I’ve answered everything but perimeter can someone please figure that out for me?


The area of rectangle WXYZ is 115. 5 in. ² what is the perimeter of triangle XYZ


Answers

The perimeter of triangle XYZ is 38.95 inches

Consider the following figure.

The area of rectangle WXYZ is 115. 5 in.²

From given figure we can observe that PQ = 4 in.

So, XW = YZ = 2 × PQ

XW = YZ = 2 × 4

XW = YZ = 8 inches

This means, the width of rectangle WXYZ is  8 inches

We know that the area of the reactngle is given by the formula,

A = length × width

here, A = 115.5 in.² and width = 8  in.

115.5 = length × 8

length = 115.5 / 8

length = 14.44 in.

So, XY = WZ =  14.44 in.

For right triangle XYZ using Pythagoras theorem,

XZ² = XY² + YZ²

XZ² = 14.44² + 8²

XZ² = XY² + YZ²

XZ² = 272.51

XZ = 16.51 in.

So, the perimeter of triangle XYZ would be,

P = XY + YZ + XZ

P = 14.44 + 8 + 16.51

P = 38.95 inches

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The amount a tree grows in one month is directly proportional to the amount of water it is given When the tree is given 23 gallons of water, it grows 4 cm that month. What is the constant of proportionality for this variation? Round your answer to the nearest thousandth

Answers

The constant of proportionality for this variation is 0.174cm/gallon .

Every relationship that always maintains the same ratio is referred to be proportionality. For instance, the average amount of apples per tree determines the proportionality between both the quantity of apples in a crop and the number of trees in the orchard.

Let the amount a tree grows in one month be - x  

The amount of water   given be -  y

If the amount a tree grows in one month is directly proportional to the amount of water given, then

x ∝ y

x = ky

k is defined as the constant of proportionality

k = [tex]\frac{x}{y}[/tex]

Given

x = 4cm

y = 23 gallons

k = [tex]\frac{4}{23}[/tex]  

k = 0.174cm/gallon

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a personal trainer analyzes the progress of her clients. so she calculates the body mass index (bmi) for each. the bmis for all of her current clients are summarized in the histogram below. histogram with 5 bars of heights 1, 3, 5, 2, 1 and bar edges of 18.1, 20.7, 23.3, 25.9, 28.5, and 31.1. the horizontal axis is labeled bmi and the vertical axis is labeled clients. she would like to offer a discount to her clients that have a current bmi of at least 25.9 in order to encourage them to keep working with her. the discount is for $50 off of their next month's training. if she were to offer these, how much total money would she give in discounts next month?

Answers

The total number of clients with a BMI of 25.9 or higher is therefore equal to 1 * 2.6 + 3 * 2

The total amount of money she would need to give in discounts next month can be found by calculating the total number of clients with a BMI of 25.9 or higher. To calculate this, the frequencies of each BMI range need to be multiplied by the width of the corresponding bar. The total amount of money she would need to give in discounts is then equal to the total number of clients with a BMI of 25.9 or higher multiplied by $50.

Using the histogram, the number of clients in each BMI range are: 18.1-20.7 (1), 20.7-23.3 (3), 23.3-25.9 (5), 25.9-28.5 (2), 28.5-31.1 (1).

The width of each bar is: 18.1-20.7 (2.6), 20.7-23.3 (2.6), 23.3-25.9 (2.6), 25.9-28.5 (2.6), 28.5-31.1 (2.6).

The total number of clients with a BMI of 25.9 or higher is therefore equal to 1 * 2.6 + 3 * 2

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If a figure is a quadrilateral, then it has four sides.

A triangle does not have four sides.

Answers

A closed quadrilateral is a kind of polygon having 4 sides, 4 vertices, and 4 angles. A triangle doesn't have four sides because if it did, it wouldn't be a triangle. It would be a quadrilateral, the term used to describe geometric objects with four sides.

Three line segments combine to form a triangle, which is a straightforward closed curve or polygon. In Euclidean geometry, any three points, notably non-collinear ones, independently create a singular triangle and a singular plane.

In Euclidean geometry, any three points, notably non-collinear ones, independently create a singular triangle and a singular plane.  polygon with 4 sides that is a quadrilateral.

One fascinating feature of a quadrilateral is that its opposite parallel sides are possible.  Four non-collinear points are joined to create it. Since a triangle would not have four sides

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Write 5y without exponents.

Answers

Answer:

Step-by-step explanation:

5y/5=y+y+y+y+y

Solve these equations for x.
-(3x - 12) = 9x -4

Answers

Answer:

x= 4/3

Step-by-step explanation:

Think the negative sign outside the parentheses as -1. Then do distributive property to the numbers inside the parentheses.

-1 x 3x and -1 x -12

That equals to -3x + 12 so now your entire equation is -3x + 12 = 9x - 4. Now lets take away 9x from both sides like this,

9x - 9x and -3x - 9x.

That equation is now -12x + 12 = -4.

Now subtract 12 from both sides like this,

12 - 12 and -4 - 12.

And then you have -12x = -16.

Now you divide both numbers by -12 like this,

-12x/-12 which equals to just x and then do -16/-12 which would equal as 1.3333 and repeating but, it can be put as 4/3 for a clearer answer.

So your answer is

x = 4/3

what is the Inequality for this?

Answers

The inequality for the goal that Miles set for the number of steps to be taken each day is x > 10, 000.

How to write the inequality ?

Mathematical expressions with inequalities are those in which the two sides are not equal. Contrary to equations, we compare two values in inequality. Less than (or less than or equal to), greater than (or greater than or equal to), or not equal to signs are used in place of the equal sign.

Miles is to take over 10, 000 steps every day which means that if the number of steps is denoted as x, the inequality would be:

x > 10, 000

This shows that the steps are greater than 10, 000 steps.

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Tomas is planning out a rail trail using a map with a marked grid. The head of the trail, which has an information kiosk, is located at (3, 0). He moves 1 unit east and 3 units north and places a pin at (4, 3) to represent the location of another information kiosk. He continues placing pins so that each pin is 1 unit east and 3 units north in relation to the previous pin. Where is the fifth information kiosk located?

Answers

Answer:

(7,12)

Step-by-step explanation:

We are add 1 to the x value each time and 3 to the y value

1st: (3,0)

2nd: (4,3)

3rd: (5,6)

4th: (6,9)

5th: (7,12)

How might I rewrite 125% of 440 is B as a simpler equation?

Answers

Answer:1.25(400)

Step-by-step explanation:

Explain whether there is enough information given in each figure to prove that the triangles are congruent using SSS or SAS. Fill in the table.

Answers

The triangles in this problem are similar using the SSS theorem.

What are similar triangles?

Similar triangles are triangles that share these following two features:

Congruent angle measures.Proportional side lengths.

For this problem, we have that the two triangles share two common angle measures.

A triangle is composed by three angles, and the sum of their measures is of 180º, hence the third angle measure will be equal for both triangles.

As the angle measures are equal, the side lengths are going to be proportional, thus the triangles are similar by the SSS theorem.

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I need help ASAP thanks if you do help!

Ty and Harrison are building signs for an upcoming craft fair. The relationship between x (the number of hours spent working) and y (the number of signs built) for each person is shown below.

Who is building signs at a faster rate?

Answers

Answer:

Harrison has the greater rate

If Ty can make 7 signs in 2 hours that means in 4 hours he could double that output to make 14 signs. Harrison, on the other hand, makes 15 signs every 4 hours.

Step-by-step explanation:

In ΔSTU, t = 390 cm, s = 900 cm and ∠S=48°. Find all possible values of ∠T, to the nearest degree

Answers

The values of ∠T is 18.78 degree.

In ΔSTU ,

We have:

T = 390 cm,

S = 900 cm

and ∠S=48°.

Using the sine rule which works law of sin with the formula:

[tex]\frac{SinT}{T} = \frac{SinS}{S}[/tex]

Plug all the values in above formula:

sinT/ 390 = sin48°/900

sin T = 0.743 × 390 / 900

sin T = 0.3220

T = [tex]sin^-^1[/tex](0.3220)

T = 18.78 degree.

Hence, The values of ∠T is 18.78 degree.

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Simplify
3√x^5/
5√x^2

Answers

Answer:

3√x^5/=15√x

   5√x^2=10√x  

Step-by-step explanation:

multiply 5 by 3.

multiply 2 by 5.

15% of the contents of a 454 gram can of dog food is protein. How many grams of protein are in the can?

Answers

Answer:

68.1 grams

Step-by-step explanation:

454 × .15 = 68.1

Please help me ASAP please please please

Answers

The two column proof to show that ABCD is a parallelogram is as shown below

How to complete two column proof?

A two-column proof is defined as a geometric proof that consists of a list of statements, and the reasons that we know those statements are true.

Statement 1; BD bisects AC

Reason 1; Given

Statement 2; ∠BAC ≅ ∠DCA

Reason 2; Given

Statement 3; AB║ CD

Reason 3; Properties of parallelogram

Statement 4; ∠BEA ≅ ∠CED

Reason 4; Alternate Interior angles

Statement 5: AE ≅ EC

Reason 5: Diagonals of a parallelogram bisect each other

Statement 6: ΔABE ≅ ΔCDE

Reason 6: SAS Congruency postulate

Statement 7: BA ≅ DC

Reason 7: Properties of parallelogram

Statement 8: ABCD is a parallelogram

Reason 8: Corresponding parts of congruent triangles are congruent

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What is the measure of the missing angle?
46°
73°
for

Answers

The third angle of the triangle must have a measure of 180° minus the sum of the other two angles, which is 180° - (46° + 73°) = 61°. Therefore, the measure of the missing angle is 61°.

What are the angles of a triangle?

The internal angles of a triangle are measured in degrees and are known as triangle angles. The sum of a triangle's angles is always 180°.

Triangle angles are classified into three types: acute angles, right angles, and obtuse angles.

An acute angle is one that is smaller than 90 degrees. This is the most common form of angle in a triangle and is regarded the most desirable.

A right angle is one that is exactly 90 degrees. This sort of angle is the most stable and sturdy in a triangle, therefore it is usually employed to make a triangle.

An obtuse angle is one that is larger than 90 degrees but less than 180 degrees. This form of angle is common in triangles, however it is less desirable than an acute angle.

The sum of the three angles of a triangle is always 180°. Acute angles are the most desirable and stable, whereas obtuse angles are present in certain triangles but are not as ideal.

In the given question,

The measure of the missing angle is 180° - (46° + 73°).

180° - (46° + 73°) = 180° - 119° = 61°

Therefore, the measure of the missing angle is 61°.

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Find the slope of a line parallel to the line whose equation is 2x+4y=56, fully simplify your answer.

Answers

Answer:

Step-by-step explanation:

m= -1/2

A large district employs 3,461 teacher. If there are 28 students per teacher, how many students are there?

Answers

Answer:

If there are 3,461 teachers and 28 students per teacher, to find the total number of students, you can multiply the number of teachers by the number of students per teacher:

3,461 teachers * 28 students/teacher = 97,268 students

So there are 97,268 students in the district.

4 is 20% of what number

Answers

Answer:

20

Step-by-step explanation:

Brianna has a points card for a movie theater.

She receives 55 rewards points just for signing up.

She earns 14. 5 points for each visit to the movie theater.

She needs at least 235 points for a free movie ticket.


Which inequality can be used to determine v, the minimum number of visits Brianna needs to earn her first free movie ticket?

Answers

The inequality 14.5v ≥ 235 can be used to determine the minimum number of visits Brianna needs to earn her first free movie ticket.

The inequality 14.5v ≥ 235 can be used to determine the minimum number of visits Brianna needs to earn her first free movie ticket.14.5v ≥ 235

To figure out how many visits Brianna needs to earn her first free movie ticket, we can set up an inequality. We'll set the left side of the equation equal to the total points needed for a free movie ticket (235 points). We'll set the right side of the equation equal to the points earned per visit (14.5 points) multiplied by the number of visits (v).

14.5v ≥ 235

The inequality 14.5v ≥ 235 can be used to determine the minimum number of visits Brianna needs to earn her first free movie ticket.

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marco made 124 free throws this season.ryan made132,if each free throw is worth 2 points,how many points did the boys score together?

Answers

Answer:

512 points altogether.

Step-by-step explanation:

This is a guess hope it helps :D

Answer:

512

Step-by-step explanation:

&:(::6)6/$/):&;!4):$:$:$:&):=512

Netflix is raising its prices from $15. 99 a month to $17. 99 a month. Mr.

Leone is annoyed and will cancel if this is more than a 20% increase in

the price. Based on this information, will he cancel? Explain.

Answers

If Netflix is raising it's prices from $15.99 a month to $17.99 a month , then Mr. Leone will not cancel his subscription because the percent increase is 12.507%    .

The old subscription price of the Netflix is = $15.99  ;

the new subscription price of Netflix is = $17.99  ;

the percent increase of Netflix can be calculated by using formula :

⇒ (new price - old price)/old price × 100 ;

substituting the values of Netflix prices ,

we get ;

⇒ (17.99 - 15.99)/15.99  × 100  ;

⇒ 2/15.99 × 100

⇒ 0.12507 × 100 ;

⇒ 12.507 % .

Therefore , the percent increase is less than 20% , so he will not cancel the Netflix Subscription .

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Noah and Lin are making paper cones to hold popcorn to hand out at a parent math night. They want the cones to hold 9π cubic inches of popcorn. What are two different possible values for height h and radius r for the cones?

Answers

The two different possible values for height h and radius r for the cones are height = 3 inches when radius = 3 inches and height = 4.5 inches when radius = 2 inches.

The volume of a cone is given by the formula [tex]V = (1/3)\pi r^2 h[/tex].

We can use this formula to find the values of h and r that will give us a cone with a volume of 9π cubic inches.

We have a volume of the cone -

(1/3)π[tex]r^2[/tex]h = 9π

solving for h, we get,

h = (3/[tex]r^2[/tex]) * 9

Now we have a formula for h in terms of r. We can substitute different values for r and see what values of h we get. Let's consider two possibilities:

case 1: r = 3 inches:

                   h = (3/[tex]3^2[/tex]) * 9 = 3 inches

case 2: r = 2 inches:

                   h = (3/[tex]2^2[/tex]) * 9 = 4.5 inches

So, one possible cone has a height of 3 inches and a radius of 3 inches, and another possible cone has a height of 4.5 inches and a radius of 2 inches.

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a fair six-sided die is tossed 300 times. find the expected value of the sample mean of the values obtained in these 300 tosses (write it up to first decimal place).

Answers

The expected value of the sample mean of the values obtained in these 300 tosses is 3.5

300 fair throws of a six-sided die are made.

The expected value of the sample mean of the results acquired from these 300 tosses must be determined.

Six sides make up a dice:

Every side of a fair dice has an equal chance of happening.

Now, each side's likelihood of being present is 1/6.

Now, the sample mean of the values collected in these 300 tosses is predicted to be equal to:

E(x) = Σx P(x =x)

= 1*1/6 + 2*1/6 + 3*1/6 + 4*1/6 + 5*1/6 + 6*1/6

= 1/6 + 2/6 + 3/6 + 4/6 + 5/6 + 6/6

= 1/6 (1+2+3+4+5+6)

= 1/6 (21)

= 21/6

E(x) = 3.5

Hence, the expected value of the sample mean of the values obtained in these 300 tosses is 3.5

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What is the Value of X

3x=17x

Answers

Answer:

14X

Step-by-step explanation:

Please help im on a time limit and i need to turn this in asap!!
Questuon:Susan works for the school newspaper and wants to conduct a survey to ask students whom they will vote for in the upcoming School elections which sample should she choose to best represent the entire population ?​

Answers

They will vote for in the upcoming School actions maybe they have to choose example should to best represent the entire population is they have to ask to every tenth student in the cafeteria.

Every Nth name from the list of target population members is chosen in systematic sampling. For instance, every tenth member on the list will be included in the sample. Thus, the 10th, 20th, 30th, and so forth will be chosen to make up the sample group.

According to this, they must consult a student in the tenth grade because he is the most knowledgeable about school and has the most experience of anybody.

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If point A (-4,5) is reflected over the line y=2 and then translated according to the rule open parentheses (x-1, y-4), what quadrant will point A be in?

Answers

The new point A(-5,1) will lie in quadrant 3.

what is the Cartesian coordinate system?

A Cartesian coordinate system in a plane is a coordinate system that specifies each point uniquely by a pair of numerical coordinates,

Given here: The point A(-4,5) is translated over y=2

Thus after the transformation( translation), the new points are

A(-4,5)→A(-4-1,5-4)=A(-5,1)

The point was translated horizontally by 1 to the left and then translated vertically by 4 units downwards.

Hence, The new point will lie in quadrant 3.

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Three lots with parallel side boundaries extend from the avenue to the boulevard find to the nearest tenth of a meter the fronteages of the lots

Answers

Three lots with parallel side boundaries extend from the avenue to the boulevard.

x + y + z = 140 meters

According to the proportion theorem,

Solving for x, using cross multiplication:

Similarly,

x/40 = z/35

solving for z by cross multiplication,

z = 35x/40

z = 7x/8

Now, the third proportions,

y/30 = z/35

Solving for y,

y = 30z/35

y = 6z/7

x + y + z = 140

4y/3 + 6z/7 +  7x/8 = 140

(224y + 144z + 147x)/168 = 140

224y + 144z + 147x = 23520

Substituting z = 7x/8,

224y + (144 × 7x/8) + 147x = 23520

224y + 126x + 147x = 23520

224y + 273x = 23520

Now,

Substitute y = 3x/4

(224×3x/4) + 273x = 23520

168x + 273x = 23520

441x = 23520

x = 53.33

Now,

We know that

y = 3x/4

so,

y = 40

And,

z = 7x/8

Z = 46.66

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Dean's savings account started with $100. After one year, it had $110. The
second year, it had $121. The third year it had $133.10.
Is a single linear model a reasonable option for this data? Yes or No?

Answers

The statement that answers the linear model possibility is NO

How to determine the true statement

From the question, we have the following parameters that can be used in our computation:

Initial = 100

Year 1 = 110

year 2 = 121

year 3 = 133.10

The savings account balance is increasing at an inconsistently increasing rate, which is not linear.

The savings account starts with $100, and increases by $10 in the first year, by $11 in the second year, and by $12.10 in the third year.

This is an example of exponential growth, which cannot be modeled by a single linear equation.

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9. Joseph is teaching a PE class today and he has a bag of balls for the students to play with.
The bag has 5 timers as many basketballs as soccer balls in the bag. If there is a total of 63 balls
in the bag, how many basketballs and soccer balls are there?

Answers

The number of basketballs and soccer balls that there are in the bag are;

Soccer balls = 10

Basketballs = 53

How to solve Algebra Word Problems?

We are told that Joseph has a bag of balls for the students to play with. The bag  has 5 times as many basketballs as soccer balls in the bag.

Let basketballs be b

Let soccer balls be s.

Thus;

b = 5s

Total number of balls is 63 balls. Thus;

5s + s = 63

6s = 63

s = 63/6

s = 10.5

b = 5(10.5)

b = 52.5

We can estimate an approximate value of s = 10 and b = 53

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