Answer:
The diameter is 6. The radius is 3. For the half of the orange circle.
The area of the half of the small orange circle is = pi*r*r = pi*3*3.
The diameter is 24. The radius is 12.
The area of the half of the light orange circle and the other colors is = pi*r*r = pi*12*12
The area of dark orange, light blue, purple and green figures = pi*12*12 – pi*3*3 = 135*pi
To get the area of the blue figure we need to divide 135*pi into ¼ and you will get the area of the blue figure.
The area of the blue figure =( ¼ )*135*pi *(1/2) = ¼ *1/2 = 1/8
The area of the blue figure is = 135pi / 8
B) outside perimeter of the window frame = 28 +pi*14 = 71.98
Hope this helps you :)
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A manager for an insurance company believes that customers have the following preferences for life insurance products: 20% prefer Whole Life, 10% prefer Universal Life, and 70% prefer Life Annuities. The results of a survey of 200 customers were tabulated. Is it possible to refute the sales manager's claimed proportions of customers who prefer each product using the data
Answer:
Yes the sales manager claims can be refuted based on the calculated percentages
Step-by-step explanation:
From the table attached below
Total number of customers = 200
Calculated percentages
customers that prefer whole life insurance = 90 = 90/200 = 45%
customers that prefer universal life insurance = 15 = 15/200 = 7.5%
customers that prefer Annuities = 95 = 95/200 = 47.5
Expected percentages:
whole life = 20%
Universal life = 10%
Life Annuities = 70%
prove that.
lim Vx (Vx+ 1 - Vx) = 1/2 X>00
Answer:
The idea is to transform the expression by multiplying [tex](\sqrt{x + 1} - \sqrt{x})[/tex] with its conjugate, [tex](\sqrt{x + 1} + \sqrt{x})[/tex].
Step-by-step explanation:
For any real number [tex]a[/tex] and [tex]b[/tex], [tex](a + b)\, (a - b) = a^{2} - b^{2}[/tex].
The factor [tex](\sqrt{x + 1} - \sqrt{x})[/tex] is irrational. However, when multiplied with its square root conjugate [tex](\sqrt{x + 1} + \sqrt{x})[/tex], the product would become rational:
[tex]\begin{aligned} & (\sqrt{x + 1} - \sqrt{x}) \, (\sqrt{x + 1} + \sqrt{x}) \\ &= (\sqrt{x + 1})^{2} -(\sqrt{x})^{2} \\ &= (x + 1) - (x) = 1\end{aligned}[/tex].
The idea is to multiply [tex]\sqrt{x}\, (\sqrt{x + 1} - \sqrt{x})[/tex] by [tex]\displaystyle \frac{\sqrt{x + 1} + \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}[/tex] so as to make it easier to take the limit.
Since [tex]\displaystyle \frac{\sqrt{x + 1} + \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}} = 1[/tex], multiplying the expression by this fraction would not change the value of the original expression.
[tex]\begin{aligned} & \lim\limits_{x \to \infty} \sqrt{x} \, (\sqrt{x + 1} - \sqrt{x}) \\ &= \lim\limits_{x \to \infty} \left[\sqrt{x} \, (\sqrt{x + 1} - \sqrt{x})\cdot \frac{\sqrt{x + 1} + \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}\right] \\ &= \lim\limits_{x \to \infty} \frac{\sqrt{x}\, ((x + 1) - x)}{\sqrt{x + 1} + \sqrt{x}} \\ &= \lim\limits_{x \to \infty} \frac{\sqrt{x}}{\sqrt{x + 1}+ \sqrt{x}}\end{aligned}[/tex].
The order of [tex]x[/tex] in both the numerator and the denominator are now both [tex](1/2)[/tex]. Hence, dividing both the numerator and the denominator by [tex]x^{(1/2)}[/tex] (same as [tex]\sqrt{x}[/tex]) would ensure that all but the constant terms would approach [tex]0[/tex] under this limit:
[tex]\begin{aligned} & \lim\limits_{x \to \infty} \sqrt{x} \, (\sqrt{x + 1} - \sqrt{x}) \\ &= \cdots\\ &= \lim\limits_{x \to \infty} \frac{\sqrt{x}}{\sqrt{x + 1}+ \sqrt{x}} \\ &= \lim\limits_{x \to \infty} \frac{\sqrt{x} / \sqrt{x}}{(\sqrt{x + 1} / \sqrt{x}) + (\sqrt{x} / \sqrt{x})} \\ &= \lim\limits_{x \to \infty}\frac{1}{\sqrt{(x / x) + (1 / x)} + 1} \\ &= \lim\limits_{x \to \infty} \frac{1}{\sqrt{1 + (1/x)} + 1}\end{aligned}[/tex].
By continuity:
[tex]\begin{aligned} & \lim\limits_{x \to \infty} \sqrt{x} \, (\sqrt{x + 1} - \sqrt{x}) \\ &= \cdots\\ &= \lim\limits_{x \to \infty} \frac{\sqrt{x}}{\sqrt{x + 1}+ \sqrt{x}} \\ &= \cdots \\ &= \lim\limits_{x \to \infty} \frac{1}{\sqrt{1 + (1/x)} + 1} \\ &= \frac{1}{\sqrt{1 + \lim\limits_{x \to \infty}(1/x)} + 1} \\ &= \frac{1}{1 + 1} \\ &= \frac{1}{2}\end{aligned}[/tex].
Answer:
Hello,
Step-by-step explanation:
[tex]\displaystyle \lim_{x \to \infty} \sqrt{x}*(\sqrt{x+1}-\sqrt{x} ) \\\\\\= \lim_{x \to \infty}\dfrac{ \sqrt{x}*(\sqrt{x+1}-\sqrt{x} )*(\sqrt{x+1}+\sqrt{x} )}{\sqrt{x+1} +\sqrt{x} } \\\\= \lim_{x \to \infty} \dfrac{\sqrt{x} *1}{\sqrt{x+1} +\sqrt{x} } \\\\\\= \lim_{x \to \infty} \dfrac{1} {\sqrt {\dfrac {x+1} {x} }+\sqrt{\dfrac{x}{x} } } \\\\\\=\dfrac{1} {\sqrt {1}+\sqrt{1} } \\\\\\=\dfrac{1} {2} \\[/tex]
Instructions: Given the following constraints, find the maximum and minimum values for
z
.
Constraints: 2−≤124+2≥0+2≤6 2x−y≤12 4x+2y≥0 x+2y≤6
Optimization Equation: =2+5
z
=
2
x
+
5
y
Maximum Value of
z
:
Minimum Value of
z
:
Answer:
z(max) = 16
z(min) = -24
Step-by-step explanation:
2x - y = 12 multiply by 2
4x - 2y = 24 (1)
4x + 2y = 0 add equations
8x = 24
x = 3
4(3) + 2y = 0
y = -6
so (3, -6) is a common point on these two lines
z = 2(3) + 5(-6) = -24
4x - 2y = 24 (1)
x + 2y = 6 add equations
5x = 30
x = 6
6 + 2y = 6
y = 0
so (6, 0) is a common point on these two lines
z = 2(6) + 5(0) = 12
4x + 2y = 0 multiply by -1
-4x - 2y = 0
x + 2y = 6 add equations
-3x = 6
x = -2
-2 + 2y = 6
y = 4
so (-2, 4) is a common point on these two lines
z = 2(-2) + 5(4) = 16
at which value will the graph of y=csc x have a zero
Answer:
y = csc(x) does not have any zero.
Step-by-step explanation:
If we have:
y = f(x)
a zero of that function would be a value x' such that:
y = f(x') = 0
Here we basically want to solve:
y = csc(x) = 0
First, remember that:
csc(x) = 1/sin(x)
now, the values of sin(x) range from -1 to 1.
So we want to solve:
1/sin(x) = 0
notice that a fraction:
a/b = 0
only if a = 0.
Then is easy to see that for our equation:
1/sin(x) = 0
The numerator is different than zero, then the equation never will be equal to zero.
Then:
y = csc(x) = 1/sin(x)
Does not have a zero.
16. Find the equation of the line that has slope m = 1/2 and passes through (4, 10).
Give your answer in slope-intercept form
Answer:
Step-by-step explanation:
Recall that the equation of a line is y = mx + b.
Excellent. Let's plug in the values we are given into the general equation for a line. We get 10 = 1/2 * 4 + b.
Simplify to 10 = 2 + b, and we get b = 8.
Our final equation, then, is y = 1/2 x + 8.
Hope this helps!
In GeoGebra, display the slope of AB and the slope of the perpendicular line passing through C. Use this to verify your responses in parts B and C. Then move points A, B, and C on the grid to several different locations, and record the slopes of the two lines and the coordinates of A, B, and C.
Answer:
plato screenshot!
Step-by-step explanation:
I don't personally know *how* to find the answers, but here's the screenshot of the suggested answer on Plato
Answer:
A B Slope of C Slope of Line Through C
(−5,4) (−1,−1) −1.25 (1,2) 0.8
(−5,4) (−3, 5) 0.5 (−2, 1) −2
(−4, 1) (−3, 5) 4 (−2, −2) −0.25
(−5, −2) (−1, 1) 0.75 (−4, 3) −1.33
(−5, −2) (1, −1) 0.17 (−3, 1) −6
Step-by-step explanation:
that way you can copy and paste each one but Plato
Find the measure of the incanted angle to the nearest degree
Answer:
15.4 degrees
Step-by-step explanation:
b= 53
h = 55
cos -¹( 53/53)= 15.4
rewrite -4<x<-1 using absolute value sign
[tex] - | 4 | < x < - |1| [/tex]
dunno if that's the desired form tough, but it states the same definition
The given inequality rewritten using absolute value sign as |-4|<x<|-1|.
What are inequalities?Inequalities are the mathematical expressions in which both sides are not equal. In inequality, unlike in equations, we compare two values. The equal sign in between is replaced by less than (or less than or equal to), greater than (or greater than or equal to), or not equal to sign.
The given inequality is -4<x<-1.
An absolute value inequality is an expression with absolute functions as well as inequality signs.
Here, using absolute value sign we get
|-4|<x<|-1|
Therefore, the given inequality rewritten using absolute value sign as |-4|<x<|-1|.
To learn more about the inequalities visit:
https://brainly.com/question/20383699.
#SPJ2
Suppose the following data represent the ratings (on a scale from 1 to 5) for a certain smart phone game, with 1 representing a poor rating. The discrete probability distribution for the random variable x is given below:
Star Frequency
1 2140
2 2853
3 4734
4 4880
5 10,715
Required:
Construct a discrete probability distribution for the random variable X
Answer:
[tex]\begin{array}{cc}{Status} & {Probability} & {1} & {0.0845} & {2} & {0.1127} & {3} & {0.1870} & {4} & {0.1927}& {5} & {0.4231} \ \end{array}[/tex]
Step-by-step explanation:
Given
The above table
Required
The discrete probability distribution
The probability of each is calculated as:
[tex]Pr = \frac{Frequency}{Total}[/tex]
Where:
[tex]Total = 2140+ 2853 + 4734 + 4880 + 10715[/tex]
[tex]Total = 25322[/tex]
So, we have:
[tex]P(1) = \frac{2140}{25322} = 0.0845[/tex]
[tex]P(2) = \frac{2853}{25322} = 0.1127[/tex]
[tex]P(3) = \frac{4734}{25322} = 0.1870[/tex]
[tex]P(4) = \frac{4880}{25322} = 0.1927[/tex]
[tex]P(5) = \frac{10715}{25322} = 0.4231[/tex]
So, the discrete probability distribution is:
[tex]\begin{array}{cc}{Status} & {Probability} & {1} & {0.0845} & {2} & {0.1127} & {3} & {0.1870} & {4} & {0.1927}& {5} & {0.4231} \ \end{array}[/tex]
Slope 0; through (-5, -1)
with steps please.
Step-by-step explanation:
0 slope means it has in x.
so the equation is y=-1, because that is the coord for the points'y axsis
Four seconds pass between the first and third flash of a strobe light. The rate at which the strobe flashes is constant. How many seconds will pass between the first and the twelfth flash of the same light?
Answer:
t = 22 s
Step-by-step explanation:
If n is the number of strobe pulses
The first strobe pulse occurs at t = 0
t = 2(n - 1)
t = 2(12 - 1)
t = 2(11)
t = 22 s
If it takes 247.2 yards of yarn to knit 2.5 baby bibs, how many yards of yarn would it take to knit 4 baby bibs? SHOW ALL WORK! ONLY ANSWER IF YOU KNOW THE ANSWER!
Answer:
395.52
Step-by-step explanation:
247.2/2.5=98.88(1 bib)
98.88x4=395.52(4 bibs)
5. a) Find the difference between the place values of two 5's in 95237508.
Answer:
4999500
Step-by-step explanation:
first 5 = 5000000
second 5 = 500
difference = 5000000-500
by solving a pair of linear equation X + Y is equal to 20 and x-y=10 the value of 'x' and 'y' are
Answer:
x=15, y=5
Step-by-step explanation:
x+y=20
x-y=10
Adding both equations;
(x+x) + (y-y) = 20+10
2x = 30
x = 30/2 = 15
Substitute x=15 into x+y=20
y= 20-x = 20-15= 5
Solve the inequality is it a,b,c,d?
Answer:
B
Step-by-step explanation:
-2/3x<31/3
x>-31/2
x>-15 1/2
Answer:
x > - 15 1/2
Step-by-step explanation:
-2/3 x -10 < 1/3
Multiply each side by 3
3(-2/3 x -10 < 1/3)
-2x -30 < 1
Add 30 to each side
-2x-30+30 <1+30
-2x < 31
Divide by -2 remembering to flip the inequality
-2x/-2 > 31/-2
x > -31/2
x > - 15 1/2
Find the time it takes for $6,400 to double when invested at an annual interest rate of 19%, compounded
continuously.
years
Find the time it takes for $640,000 to double when invested at an annual interest rate of 19%, compounded
continuously.
years
Give your answers accurate to 4 decimal places.
Question Holn Video M Message instructor
9514 1404 393
Answer:
3.6481 years
Step-by-step explanation:
The doubling time is not a function of the amount invested. It can be found by considering the account balance multiplier:
2 = e^(rt) = e^(0.19t)
Taking logs, we can solve for t:
ln(2) = 0.19t
t = ln(2)/0.19 ≈ 3.6481431
Rounded to 4 decimal places, the doubling time is 3.6481 years, for either balance.
The triangles are similar, find y
Answer:
y = 3.6
x = 3.5
Step-by-step explanation:
The triangles are similar.
[tex]\frac{3}{2.4} = \frac{x}{2.8} = \frac{4.5}{y}[/tex]
Find y:
[tex]\frac{4.5}{y} = \frac{5}{4}[/tex]
[tex]4.5 * 4 = 5y => 18 = 5y => y = 3.6[/tex]
Find x:
[tex]\frac{x}{2.8} = \frac{5}{4}[/tex]
[tex]2.8 * 5 = 4x => 14 = 4x => x = 3.5[/tex]
Help please. I need the answer
I will give brainliest. I need help ASAP.
Answer:
\I got not answer cause im da BUDDHA
But gimme brainliest squekky plssss
The cost of producing x units of a particular commodity is 2 C(x) = x' +6x +45 shillings, and the production level t hours into a particular production run is x(1)=0.312 +0.04 units. At what rate is cost changing with respect to time after 5 hours?
Complete question is;
The cost of producing x units of a particular commodity is C(x) = ⅔x² + 6x + 45 shillings and the production level t hours into a particular production run is x(t) = 0.3t² + 0.04t. At what rate is cost changing with respect to time after 5 hours?
Answer:
dC/dt = 49.45
Step-by-step explanation:
Since C(x) = ⅔x² + 6x + 45
And x(t) = 0.3t² + 0.04t
This means that;
C(x) = C(x(t))
The rate at what cost is changing with respect to time is given as;
dC/dt
Thus, from chain rule;
dC/dt = (dC/dx) × (dx/dt)
dC/dx = (4/3)x + 6
dx/dt = 0.6t + 0.04
Now, when t = 5, then;
x(5) = 0.3(5)² + 0.04(5)
x = 7.7
Thus;
dC/dx = (4/3)x + 6 = (4/3)(7.7) + 6 = 16.267
At 5 hours,
dx/dt = 0.6(5) + 0.04 = 3.04
Thus;
dC/dt = 16.267 × 3.04
dC/dt = 49.45
People were asked if they owned an artificial Christmas tree. Of 78 people who lived in an apartment, 38 own an artificial Christmas tree. Also it was learned that of 84 people who own their home, 46 own an artificial Christmas tree. Is there a significant difference in the proportion of apartment dwellers and home owners who own artificial Christmas trees
Answer:
The p-value of the test is 0.4414, higher than the standard significance level of 0.05, which means that there is not a a significant difference in the proportion of apartment dwellers and home owners who own artificial Christmas trees.
Step-by-step explanation:
Before testing the hypothesis, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Apartment:
38 out of 78, so:
[tex]p_A = \frac{38}{78} = 0.4872[/tex]
[tex]s_A = \sqrt{\frac{0.4872*0.5128}{78}} = 0.0566[/tex]
Home:
46 out of 84, so:
[tex]p_H = \frac{46}{84} = 0.5476[/tex]
[tex]s_H = \sqrt{\frac{0.5476*0.4524}{84}} = 0.0543[/tex]
Test if the there a significant difference in the proportion of apartment dwellers and home owners who own artificial Christmas trees:
At the null hypothesis, we test if there is no difference, that is, the subtraction of the proportions is equal to 0, so:
[tex]H_0: p_A - p_H = 0[/tex]
At the alternative hypothesis, we test if there is a difference, that is, the subtraction of the proportions is different of 0, so:
[tex]H_1: p_A - p_H \neq 0[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
From the samples:
[tex]X = p_A - p_H = 0.4872 - 0.5476 = -0.0604[/tex]
[tex]s = \sqrt{s_A^2 + s_H^2} = \sqrt{0.0566^2 + 0.0543^2} = 0.0784[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{-0.0604 - 0}{0.0784}[/tex]
[tex]z = -0.77[/tex]
P-value of the test and decision:
The p-value of the test is the probability of the difference being of at least 0.0604, to either side, plus or minus, which is P(|z| > 0.77), given by 2 multiplied by the p-value of z = -0.77.
Looking at the z-table, z = -0.77 has a p-value of 0.2207.
2*0.2207 = 0.4414
The p-value of the test is 0.4414, higher than the standard significance level of 0.05, which means that there is not a a significant difference in the proportion of apartment dwellers and home owners who own artificial Christmas trees.
Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular type, its mean value and standard deviation are 75 GPa and 1.7 GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.)
Required:
a. Calculate P(79 <= P <= 81) when n = 25.
b. How likely is it that the sample mean diameter exceeds 81 when n = 36?
Answer:
a) P(79 <= P <= 81) = 0.9968
b) P( X > 81 ) = 0.0002
Step-by-step explanation:
mean value = 75 GPa
standard deviation = 1.7 GPa
a) Determine P(79 <= P <= 81)
given that : n = 25
attached below is the detailed solution
P(79 <= P <= 81) = 0.9968
b) Determine how likely the sample mean diameter will exceed 81
given that n = 36
mean diameter = 81
P( X > 81 ) = 0.0002
Write the equation in vertex form of the parabola with the vertex (-4,-4) that goes through the point (-2,-16)
Answer:
[tex] - 3(x + 4) {}^{2} - 4[/tex]
Step-by-step explanation:
Vertex form is
[tex]a(x - h) {}^{2} + k = f(x)[/tex]
We know that h and k are both -4. Let x be -2 and y be -16.
[tex]a( - 2 + 4) {}^{2} - 4 = - 16[/tex]
[tex]a(2) {}^{2} - 4 = - 16[/tex]
[tex]4a - 4 = - 16[/tex]
[tex]4a = - 12[/tex]
[tex]a = - 3[/tex]
So the equation in vertex form is
[tex] - 3(x + 4) {}^{2} - 4[/tex]
a store sells pencils pens and markers that sells two times as many markers as pencils and three times as many pens as pencils is the store sells a total of 1950 pencils and pens and markers in a week how many of each were sold
Answer:
Pencils = 325 ; Pens = 975 ; Markers = 650
Step-by-step explanation:
Let :
Number of Pencils = x
Number of pens = y
Number of markers = z
2 times as many markers as pencils
z = 2x
3 times as many pens as pencils
y = 3x
x + y + z = 1950
Write z and y in terms of x in the equation :
x + 3x + 2x = 1950
6x = 1950
Divide both sides by 6
6x / 6 = 1950 / 6
x = 325
Number of pencils = 325
Pens = 3 * 325 = 975
Markers = 2 * 325 = 650
Pencils = 325 ; Pens = 975 ; Markers = 650
Maybe you have considered buying a term life insurance policy. The expected value of any term life insurance product yields a positive expected value for the insurance company and a negative expected value for you, meaning the insurance company will make profits by selling their insurance products. Would you still buy the term life insurance? Why or why not? Are there other examples other than insurance that uses this same concept?
Answer:
Yes one should consider to buy the policy as important to have insured plan that help at the time of need.
Step-by-step explanation:
Term of life insurance is a form of life insurance which guarantees the payment of the stated death benefit. If the person des during the plan the term expires. The policy has no value other than guarantee benefits. The term life insurance will make products by selling products and thus it's necessary to have insurance. Health, age, and life expectancy are some of the points that need to consider for buying plans.what is 9 divided by 7
Answer: 1.28571428571. This number is infinite.
Step-by-step explanation:
Answer:
1.29 rounded
Step-by-step explanation:
5/3=12/x what does x equal?
[tex] \frac{5}{3} = \frac{12}{x} \\ = > \frac{5x}{3} = 12 \\ = > 5x = 12 \times 3 \\ = > 5x = 36 \\ = > x = \frac{36}{5} \\ = > x = 7.2[/tex]
This is the answer.
The function below models the correlation between the number of hours a plant is kept in sunlight (x) and the height (y), in mm, to which it grows: y = 2 + 4x What does the y-intercept of this function represent? (1 point) The original height of the plant was 4 mm. The original height of the plant was 2 mm. The height of the plant increases by 2 mm for every hour of sunlight it receives. The height of the plant increases by 4 mm for every hour of sunlight it receives.
Answer:
The original height of the plant was 2 mm
Step-by-step explanation:
Given
[tex]y = 2 + 4x[/tex]
Required
Interpret the y-intercept
The y-intercept is when [tex]x = 0[/tex]
So, we have:
[tex]y = 2 + 4 *0[/tex]
[tex]y = 2 + 0[/tex]
[tex]y = 2[/tex]
This implies that the original or initial height was 2 mm
A construction crane lifts a bucket of sand originally weighing 145 lbs at a constant rate. Sand is lost from the bucket at a constant rate of .5lbs/ft. How much work is done in lifting the sand 80ft?
Answer: [tex]10,000\ lb.ft[/tex]
Step-by-step explanation:
Given
Initial weight of the bucket is [tex]145\ lb[/tex]
It is lifted at constant rate and rate of sand escaping is [tex]0.5\ lb/ft[/tex]
At any height weight of the sand is [tex]w(h)=145-0.5h[/tex]
Work done is given by the product of applied force and displacement or the area under weight-displacement graph
from the figure area is given by
[tex]\Rightarrow W=\int_{0}^{80}\left ( 145-0.5h \right )dh\\\\\Rightarrow W=\left | 145h-\dfrac{0.5h^2}{2} \right |_0^{80}\\\\\Rightarrow W=\left [ 145\times 80-\dfrac{0.5(80))^2}{2} \right ]-0\\\\\Rightarrow W=11,600-1600\\\\\Rightarrow W=10,000\ lb.ft[/tex]