Answer:
900
Step-by-step explanation:
Which equation can be used to find the area of the rectangle? A. A=9+4 B. A=1/2 (9)(4) C. A=9+9+4+4 D. A=(9)(4)
Answer:
D. A=(9)(4)
Step-by-step explanation:
area= length x width = 9x4
Need help with this as soon as possible
Answer:
Step-by-step explanation:
[tex]\frac{14}{x} =14/x[/tex]
Thus, we can multiply both sides by x to get 14=0. Because 14 does not equal 0, the equation has no solutions. A value of x that makes the equation false is 541, which makes the simplified equation turn into 14=0.
Another value of x that makes the equation false is 7, which makes the simplified equation turn into 14=0.
Hope it helps <3
Show all work to solve 3x^2 – 5x – 2 = 0.
Answer:
Step-by-step explanation:
3x2−5x−2=0
For this equation: a=3, b=-5, c=-2
3x2+−5x+−2=0
Step 1: Use quadratic formula with a=3, b=-5, c=-2.
x= (−b±√b2−4ac )2a
x= (−(−5)±√(−5)2−4(3)(−2) )/2(3)
x= (5±√49 )/6
x=2 or x= −1 /3
Answer:
x=2 or x= −1/ 3
The solutions to the equation are x = -1/3 and x = 2.
Here are the steps on how to solve [tex]3x^{2}[/tex] – 5x – 2 = 0:
First, we need to factor the polynomial. The factors of 3 are 1, 3, and the factors of -2 are -1, 2. The coefficient on the x term is -5, so we need to find two numbers that add up to -5 and multiply to -2. The two numbers -1 and 2 satisfy both conditions, so the factored polynomial is (3x + 1)(x - 2).
Next, we set each factor equal to 0 and solve for x.
(3x + 1)(x - 2) = 0
3x + 1 = 0
3x = -1
x = -1/3
x - 2 = 0
x = 2
Therefore, the solutions to the equation [tex]3x^{2}[/tex] – 5x – 2 = 0 are x = -1/3 and x = 2.
Here is the explanation for each of the steps:
Step 1: In order to factor the polynomial, we need to find two numbers that add up to -5 and multiply to -2. The two numbers -1 and 2 satisfy both conditions, so the factored polynomial is (3x + 1)(x - 2).
Step 2: We set each factor equal to 0 and solve for x. When we set 3x + 1 equal to 0, we get x = -1/3. When we set x - 2 equal to 0, we get x = 2. Therefore, the solutions to the equation are x = -1/3 and x = 2.
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[tex]\frac{d}{7}[/tex] + –59 = –50
d = _______
A restaurant has a main location and a traveling food truck. The first matrix A shows the number of managers and associates employed. The second matrix B shows the average annual cost of salary and benefits (in thousands of dollars). Complete parts (a) through (c) below.
Managers Associates
Restaurant 5 25 = A
Food Truck 1 4
Salary Benefits
Managers 41 6 = B
Associates 20 2
a. Find the matrix product AB .
b. Explain what AB represents.
c. According to matrix AB , what is the total cost of salaries for all employees (managers and associates) at the restaurant? What is the total cost of benefits for all employees at the food truck?
Answer:
A*B= [tex]\left[\begin{array}{cc}705&80\\121&14 \end{array}\right][/tex]
Step-by-step explanation:
Given A= [tex]\left[\begin{array}{cc}5&25\\1&4\end{array}\right] \left[\begin{array}{cc}41&6\\20&2\end{array}\right][/tex] = B
Finding A*B means multiplying the first row with the first column and first row with the second column would give the first row elements. The second ro0w elements are obtained by multiplying the second row with the 1st column and second row with the second column.
so A*B= [tex]\left[\begin{array}{cc}5*41+ 25*20&5*6 + 25*2\\ 1*41+4*20 & 1*6+ 4*2\end{array}\right][/tex]
Now multiply and add the separate elements of the matrix A*B=
[tex]\left[\begin{array}{cc}205+500&30+50\\41+80&6+8\end{array}\right][/tex]
A*B= [tex]\left[\begin{array}{cc}705&80\\121&14 \end{array}\right][/tex]
b. The 1st element of the 1st row shows the salaries of the managers and 2nd element of the 1st row the salaries of associates at the restaurant . The second row 1 st element shows the benefits of the managers and 2nd element the benefits of the associates at the food truck.
c. The total cost of salaries for all employees (managers and associates) at the restaurant = 705 + 80 = 785
Total cost of benefits for all employees at the food truck= 121 + 14= 135
I NEED HELP FAST, THANKS! :)
Answer:
33 units²
Step-by-step explanation:
A (graphing) calculator shows you that f(4) ≈ 8, and f(8) ≈ 8.5. The curve is almost a straight line between, so the area is approximately ...
A = (1/2)(8 + 8.5)(4) = 33
__
If you do the integration, it gets a bit messy.
[tex]\displaystyle\dfrac{5}{7}\int_4^8{x^{2/7}}\,dx+\dfrac{1}{2}\int_4^8{x^{4/9}}\,dx+\int_4^8{6}\,dx\\\\=\left.\left(\dfrac{5}{9}x^{9/7}+\dfrac{9}{26}x^{13/9}+6x\right)\right|_4^8\approx 33.16[/tex]
The appropriate answer choice is 33 square units.
In 12 years, a bond with a 6.35% annual rate earned $7620 as simple interest. What was the principle amount of the bond
Answer:
The principal amount is $10160
Step-by-step explanation:
Given; Simple interest, I = 7620
Rate, R = 6.25
Time, T = 12
Principal, P =?
The formula for simple interest, I is;
[tex]I = \frac{PRT}{100}[/tex]
Making P the subject of formula;
[tex]P = \frac{I100}{RT}[/tex]
[tex]P = \frac{7620 *100}{6.25*12}[/tex]
[tex]P = \frac{762000}{75}\\P = 10160[/tex]
Therefore, the principal amount is $10160
Answer:
10000
Step-by-step explanation:
If an amount of money, P, called the principal, is invested for a period of t years at an annual interest rate r, the amount of simple interest, I, earned is given by
I=PrtwhereIPrt=interest=principal=rate=time
The following information is given.
Irt=$7,620=0.0635=12 years
Substituting the given information into the simple interest formula and solving for P gives
7,6207,620=(P)(0.0635)(12)=0.762P
Dividing both sides by 0.762, we have
P=7,6200.762=10,000
Thus, the principal amount of the bond was $10,000.
1)
Check all the expressions that are equal to this one:
5. (4+1)
A. (5 • 4) + 1
B. 5.4 + 5 - 1
C. (4+1) • 5
D. 5. (1 + 4)
An object moves along a horizontal coordinate line in such a way that its position at time t is specified by s equals t cubed minus 3 t squared minus 24 t plus 8. Here s is measured in centimeters and t in seconds. When is the object slowing down; that is, when is its speed decreasing?
Answer:
a)
The object slowing down S = -72 centimetres after t = 4 seconds
b)
The speed is decreasing at t = -2 seconds
The objective function S = 36 centimetres
Step-by-step explanation:
Step(i):-
Given S = t³ - 3 t² - 24 t + 8 ...(i)
Differentiating equation (i) with respective to 'x'
[tex]\frac{dS}{dt} = 3 t^{2} - 3 (2 t) - 24[/tex]
Equating Zero
3 t ² - 6 t - 24 = 0
⇒ t² - 2 t - 8 = 0
⇒ t² - 4 t + 2 t - 8 = 0
⇒ t (t-4) + 2 (t -4) =0
⇒ ( t + 2) ( t -4) =0
⇒ t = -2 and t = 4
Again differentiating with respective to 'x'
[tex]\frac{d^{2} S}{dt^{2} } = 6 t - 6[/tex]
Step(ii):-
Case(i):-
Put t= -2
[tex]\frac{d^{2} S}{dt^{2} } = 6 t - 6 = 6 ( -2) -6 = -12 -6 = -18 <0[/tex]
The maximum object
S = t³ - 3 t² - 24 t + 8
S = ( -2)³ - 3 (-2)² -24(-2) +8
S = -8-3(4) +48 +8
S = - 8 - 12 + 56
S = - 20 +56
S = 36
Case(ii):-
put t = 4
[tex]\frac{d^{2} S}{dt^{2} } = 6 t - 6 = 6 ( 4) -6 = 24 -6 = 18 >0[/tex]
The object slowing down at t =4 seconds
The minimum objective function
S = t³ - 3 t² - 24 t + 8
S = ( 4)³ - 3 (4)² -24(4) +8
S = 64 -48 - 96 +8
S = - 72
The object slowing down S = -72 centimetres after t = 4 seconds
Final answer:-
The object slowing down S = -72 centimetres after t = 4 seconds
The speed is decreasing at t = -2 seconds
The objective function S = 36 centimetres
Denise is planning to put a deck in her back yard. The deck will be a 10-by-7-foot rectangle with a semicircle of diameter 4 feet, as shown below. Find the area of the deck (in square feet).(round your answer to two decimal places)
Answer:
[tex]approx. = 85.28 {ft}^{2} [/tex]
Step-by-step explanation:
You can think of this as adding the area of the rectangular portion of the deck (length x width) and the semicircular portion (πr^2)/2.
(l×w)+(πr^2)/2
(10×7)+((π2^2)/2
79+2π
[tex]approx. = 85.28 {ft}^{2} [/tex]
I NEED HELP PLEASE, THANKS! :)
A music concert is organized at a memorial auditorium. The first row of the auditorium has 16 seats, the second row has 24 seats, the third row has 32 seats, and so on, increasing by 8 seats each row for a total of 50 rows. Find the number of people that can be accommodated in the sixteenth row. (Show work)
Answer: 136
Step-by-step explanation:
An= A1+(n-1)d
A1=16, d=8, and n=16
A16= 16 +(16-1)(8)
A16= 16(15)(8)
A16= 16+120
A16=136
Hey there! :)
Answer:
f(16) = 136 seats.
Step-by-step explanation:
This situation can be expressed as an explicit function where 'n' is the row number.
The question also states that the number of seats increases by 8. Use this in the equation:
f(n) = 16 + 8(n-1)
Solve for the number of seats in the 16th row by plugging in 16 for n:
f(16) = 16 + 8(16-1)
f(16) = 16 + 8(15)
f(16) = 16 + 120
f(16) = 136 seats.
Does the following systems produce an infinite number of solutions 2y + x = 4 ; 2y = -x +4
Answer:
Yes.
Step-by-step explanation:
In the future, simply plug both equations into Desmos.
A rectangular park measuring 32 yards by 24 yards is surrounded by a trail of uniform width. If the area of the park and the trail combine is 1748 square yards, what is the width of the park
Answer:
The width = 38 yard
Step-by-step explanation:
Given
Dimension of Park = 32 by 24 yard
Area = 1748 yd²
Required
Find the width of the park
Given that the park is surrounded by a trail;
Let the distance between the park and the trail be represented with y;
Such that, the dimension of the park becomes (32 + y + y) by (24 + y + y) because it is surrounded on all sides
Area of rectangle is calculated as thus;
Area = Length * Width
Substitute 1748 for area; 32 + 2y and 24 + 2y for length and width
The formula becomes
[tex]1748 = (32 + 2y) * (24 +2y)[/tex]
Open Bracket
[tex]1748 = 32(24 + 2y) + 2y(24 + 2y)[/tex]
[tex]1748 = 768 + 64y + 48y + 4y^2[/tex]
[tex]1748 = 768 + 112y + 4y^2[/tex]
Subtract 1748 from both sides
[tex]1748 -1748 = 768 -1748 + 112y + 4y^2[/tex]
[tex]0 = 768 -1748 + 112y + 4y^2[/tex]
[tex]0 = -980 + 112y + 4y^2[/tex]
Rearrange
[tex]4y^2 + 112y -980 = 0[/tex]
Divide through by 4
[tex]y^2 + 28y - 245 = 0[/tex]
Expand
[tex]y^2 + 35y -7y - 245 = 0[/tex]
Factorize
[tex]y(y+35) - 7(y + 35) = 0[/tex]
[tex](y-7)(y+35) = 0[/tex]
Split the above into two
[tex]y - 7 = 0\ or\ y + 35 = 0[/tex]
[tex]y = 7\ or\ y = -35[/tex]
But y can't be less than 0;
[tex]So,\ y = 7[/tex]
Recall that the dimension of the park is 32 + 2y by 24 + 2y
So, the dimension becomes 32 + 2*7 by 24 + 2*7
Dimension = 32 + 14 yard by 24 + 14 yard
Dimension = 46 yard by 38 yard
Hence, the width = 38 yard
If two variables, x and y, have a very strong linear relationship, then:______. a. there is evidence that x causes a change in y.b. there is evidence that y causes a change in x.c. there might not be any causal relationship between x and y.d. none of these alternatives is correct.
Answer:
c. there might not be any causal relationship between x and y.
Step-by-step explanation:
A correlation can be defined as a numerical measure of the relationship between existing between two variables (x and y).
In Mathematics and Statistics, a group of data can either be negatively correlated, positively correlated or not correlated at all.
1. For a negative correlation: a set of values in a data increases, when the other set begins to decrease. Here, the correlation coefficient is less than zero (0).
2. For a positive correlation: a set of values in a data increases, when the other set also increases. Here, the correlation coefficient is greater than zero (0).
3. For no or zero correlation: a set of values in a data has no effect on the other set. Here, the correlation coefficient is equal to zero (0).
If two variables, x and y, have a very strong linear relationship, then there might not be any causal relationship between x and y.
A causal relation exists between two variables (x and y), if the occurrence of the first causes the other; where, the first variable (x) is referred to as the cause while the second variable (y) is the effect.
A strong linear relationship exists between two variables (x and y), if they both increases or decreases at the same time. It usually has a correlation coefficient greater than zero or a slope of 1.
Hence, if two variables, x and y, have a very strong linear relationship, then there might not be any causal relationship between x and y.
HELP ASAP! The number of entertainment websites in 1995 wass 54. By 2004 there were 793 entertainment website..
Approximately, what was the rate of change for the number of the websites for this time period??
=============================================================
How I got that answer:
We have gone from 54 websites to 793 websites. This is a change of 793-54 = 739 new websites. This is over a timespan of 2004-1995 = 9 years.
Since we have 739 new websites over the course of 9 years, this means the rate of change is 739/9 = 82.1111... where the '1's go on forever. Rounding to the nearest whole number gets us roughly 82 websites a year.
----------
You could use the slope formula to get the job done. This is because the slope represents the rise over run
slope = rise/run
The rise is how much the number of websites have gone up or down. The run is the amount of time that has passed by. So slope = rise/run = 739/9 = 82.111...
In a more written out way, the steps would be
slope = rise/run
slope = (y2-y1)/(x2-x1)
slope = (793 - 54)/(2004 - 1995)
slope = 739/9
slope = 82.111....
by how much is 25% of #25 greater than 15% of #15
Answer:
4
Step-by-step explanation:
25% of 25
0.25 × 25 = 6.25
15% of 15
0.15 × 15 = 2.25
Find the difference.
6.25 - 2.25
= 4
Write the value of the money in dollars Brainliest Awnser gets 7 points for greatness
Answer:
The picture isn't very clear but I think this is the answer.
1. 15 cents
2. $1.31
3. 30 cents
Step-by-step explanation:
1. 10+5
2. 50+50+10+10+10+1
3. 25+5
The pair of figures is similar. Find x. Round to the nearest tenth if necessary.
0.1 ft
4.5 ft
0.9 ft
4 ft
Answer:
x = 4.5 ft
Step-by-step explanation:
Since the figures are similar then the ratios of corresponding sides are equal, that is
[tex]\frac{18}{x}[/tex] = [tex]\frac{8}{2}[/tex] ( cross- multiply )
8x = 36 ( divide both sides by 8 )
x = 4.5
Using the matrix solver on your calculator, find the solution to the system of
equations shown below.
3x - y = 4
6x - 2y = 7
A. x = 6, y = 2
B. No solution
C. x= 3, y= 1
D. More than 1 solution
SUBMIT
Answer:
B. No solution.
Step-by-step example
I will try to solve your system of equations.
3x−y=4;6x−2y=7
Step: Solve3x−y=4for y:
3x−y+−3x=4+−3x(Add -3x to both sides)
−y=−3x+4
−y
−1
=
−3x+4
−1
(Divide both sides by -1)
y=3x−4
Step: Substitute3x−4foryin6x−2y=7:
6x−2y=7
6x−2(3x−4)=7
8=7(Simplify both sides of the equation)
8+−8=7+−8(Add -8 to both sides)
0=−1
Therefore, there is no solution, and the lines are parallel.
The manager of a mall conducted a survey among two groups (n1 = 100, n2 = 100) of visitors to the mall on different days. She found that the first group spent an average of 60 minutes in the mall, while the second group spent an average of 90 minutes in the mall. If the manager wishes to see the difference in the average times spent by the two groups in the mall,
Which of the following could be the alternative hypothesis?
a. The difference in the average times spent by the two groups in the mall is 30 minutes.
b. There is at least some difference in the average times spent by the two groups in the mall.
c. There is a difference in the average times spent by the two groups in the mall, with a standard deviation of 30 minutes.
d. There is no difference in the average times spent by the two groups in the mall.
Answer:
Option B - There is at least some difference in the average times spent by the two groups in the mall.
Step-by-step explanation:
A null hypothesis is a hypothesis that states that there is no statistical significance between the two variables. Thus, It is usually the hypothesis that a researcher or experimenter will try to disprove or discredit. While an alternative hypothesis is one that states there is a statistically significant relationship between two variables.
Now, applying these definitions to the question, we can see that;
Null Hypothesis is;
H0; There is no difference in the average times spent by the two groups in the mall
While the alternative hypothesis is;
Ha; There is at least some difference in the average times spent by the two groups in the mall
Thus, correct answer is option B
Answer:
It is option b
Step-by-step explanation:
pls pls help me help me help me
Answer:
2
Step-by-step explanation:
Answer:
I hope it will help you....
HELPPPPPP!!!!!!!!!! ITS DUENSOON PLS
Answer:
Step-by-step explanation:
A=2(3.14)rh+2(3.14)r^2
A=2(3.14)(4.5)(19)+2(3.14)(4.5)^2
A=536.94+127.17
A=664.11
Might want to double the math but the formula is right!
Find the percent of increase. Original Price: $200 Retail Price: $250
Answer:
The percent of increase is 25%
Step-by-step explanation:
Percentage increase = increase in price/original price × 100 = ($250 - $200)/$200 × 100 = $50/$200 × 100 = 25%
Evaluate the expression ........
Answer:
13
Step-by-step explanation:
p^2 -6p +6
Let p=-1
(-1)^2 -6(-1) +6
1 +6+6
13
What is the point-slope form of a line with slope 3/2 that contains the point
(-1,2)?
A. y+2 = (x - 1)
B. y-2 = {(x-1)
C. y-2 = = {(x+1)
D. y+2= {(x+1)
Answer:
y - 2 = (3/2)(x + 1)
Step-by-step explanation:
Start with the point-slope formula y - k = m(x - h). With m = 3/2, h = -1 and k = 2, we get:
y - 2 = (3/2)(x + 1)
suppose we have a fuse box containing 40 fuses of which 6 are defectives. If two fuses are selected at random and removed from the box. Find the probability that both are defective, if the first fuse (a) Replaced (b) Not replaced.
Answer: a) P(1&2 =defect)= 1/800
b) P(1&2 =defect)= 1/780
Step-by-step explanation:
a) The probability that 1st of the selected fuses is defective is 2/40=1/20 =0.05
So if we replace it by the not defective the number of defective fuses is 1 and total number is 40.
So the probability that 2-nd selected fuse is defective as well is 1/40
The probability both fuses are defective is
P(1&2 =defect)= 2/40*1/40=2/1600=1/800
b) The probability that 1st of the selected fuses is defective is 2/40=1/20 =0.05
SO residual amount of the fuses is 39. 1 of them is defective.
So the probability that 2-nd selected fuse is defective as well is 1/39
The probability both fuses are defective is
P(1&2 =defect)= 2/40*1/39=2/1560=1/780
According to a recent study, some experts believe that 15% of all freshwater fish in a particular country have such high levels of mercury that they are dangerous to eat. Suppose a fish market has 150 fish we consider randomly sampled from the population of edible freshwater fish. Use the Central Limit Theorem (and the Empirical Rule) to find the approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15. You can use the Central Limit Theorem because the fish were randomly sampled; the population is more than 10 times 150; and n times p is 22.5, and n times (1 minus p) is 127.5, and both are more than 10.
Answer:
The approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15 is 0.95.
Step-by-step explanation:
According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.
The mean of this sampling distribution of sample proportion is:
[tex]\mu_{\hat p}=0.15[/tex]
The standard deviation of this sampling distribution of sample proportion is:
[tex]\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}[/tex]
As the sample size is large, i.e. n = 150 > 30, the central limit theorem can be used to approximate the sampling distribution of sample proportion by the normal distribution.
Compute the mean and standard deviation as follows:
[tex]\mu_{\hat p}=0.15\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.15(1-0.15)}{150}}=0.0292[/tex]
So, [tex]\hat p\sim N(0.15, 0.0292^{2})[/tex]
In statistics, the 68–95–99.7 rule, also recognized as the empirical rule, is a shortcut used to recall that 68%, 95% and 99.7% of the Normal distribution lie within one, two and three standard deviations of the mean, respectively.
Then,
P (µ-σ < X < µ+σ) ≈ 0.68
P (µ-2σ <X < µ+2σ) ≈ 0.95
P (µ-3σ <X < µ+3σ) ≈ 0.997
Then the approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.15 is 0.95.
That is:
[tex]P(\mu_{\hat p}-2\sigma_{\hat p}<\hat p<\mu_{\hat p}+2\sigma_{\hat p})=0.95\\\\P(0.15-2\cdot0.0292<\hat p<0.15+2\cdot0.0292)=0.95\\\\P(0.092<\hat p<0.208)=0.95[/tex]
How do you write 0.0683 in scientific notation? ____× 10^____
Answer:
It's written as
[tex]6.83 \times {10}^{ - 2} [/tex]
Hope this helps you
Answer:
6.83 × 10 -2
hopefully this helped :3
ope Equation
fy
What is the equation of the line in point-slope form?
4
= {(x + 4)
Oy+4=;
O y-4 = 2(x + 4)
N
Oy - 0 = 2(x-4)
Oy - 4 = 2(x -0)
4
-2.
2.
Answer:
A
Step-by-step explanation:
For point-slope form, you need a point and the slope.
y - y₁ = m(x - x₁)
Looking at the graph, the points you have are (4, 0) and (-4, -4). You can use these points to find the slope. Divide the difference of the y's by the difference of the x's/
-4 - 0 = -4
-4 - 4 = -8
-4/-8 = 1/2
The slope is 1/2. This cancels out choices C and D.
With the point (-4, -4), A is the answer.
the equation of the line in slope-intercept form is:
y = (1/2)x - 2
What is the Linear equation?A linear equation is an algebraic equation of the form y=mx+b, where m is the slope and b is the y-intercept, and only a constant and a first-order (linear) term are included. Sometimes, the aforementioned is referred to as a "linear equation of two variables," with y and x serving as the variables.
From the graph, two points on the line are (-4, -4) and (4,0),
The formula for the slope of a line is:
m = (y₂ - y₁) / (x₁ - x₁)
where (x₁, y₁) and (x₂, y₂) are two points on the line.
Using the given points (-4, -4) and (4, 0), we can calculate the slope:
m = (0 - (-4)) / (4 - (-4))
m = 4 / 8
m = 1/2
Now that we know the slope, we can use the slope-intercept form of a line, which is:
y = mx + b
where m is the slope and b is the y-intercept.
To find the y-intercept, we can use one of the given points on the line. Let's use the point (-4, -4):
y = mx + b
-4 = (1/2)(-4) + b
-4 = -2 + b
b = -2
Therefore, the slope-intercept form of the line is y = (1/2)x - 2.
Learn more about Linear equations here:
https://brainly.com/question/11897796
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The half-life of radium-226 is 1590 years. If a sample contains 400 mg how many mg will remain after 4000 years?
Answer:
69.9 mg
Step-by-step explanation:
A = A₀ (½)^(t / T)
where A is the final amount,
A₀ is the initial amount,
t is time,
and T is the half life.
A = 400 (½)^(4000 / 1590)
A = 69.9 mg