Two large containers A and B of the same size are filled with different fluids. The fluids in containers A and B are maintained at 0° C and 100° C, respectively. A small metal bar, whose initial temperature is 100° C, is lowered into container A. After 1 minute the temperature of the bar is 90° C. After 2 minutes the bar is removed and instantly transferred to the other container. After 1 minute in container B, the temperature of the bar rises 10o. How long, measured from the start of the entire process, will it take the bar to reach 99.5° C?
A small metal bar, whose initial temperature was 30° C, is dropped into a large container of boiling water. How long will it take the bar to reach 80° C if it is known that its temperature increases 2° during the first second? (The boiling temperature for water is 100° C. Round your answer to one decimal place.) sec How long will it take the bar to reach 95° C? (Round your answer to one decimal place.) sec
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A person starts walking from home and walks:
3 miles East
5 miles Southeast
6 miles South
2 miles Southwest
3 miles East
A. Find the total displacement vector for this walk: _ i+_ j
B. If this person walked straight home, they'd have to walk ___ Miles
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We have a parametric curve x = - 6t + t^3 + 1, y = -2t − t^2
a) Sketch a graph of the curve (use technology to help)
b) Find the equation of the tangent line at t = –1
c) Find the value(s) of t where the tangent is horizontal.
d) Find the value(s) of t where the tangent is vertical.
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Find the maximum profit given by the revenue and cost functions below, where x is in thousands of units and R(x) and C(x) are in thousands of dollars.
R(x)= 115x-x^2
c(x)=1/3x^3-6x^2+91x+38
A. 682 thousand dollars
B. 470 Thousand dollars
C. 394 thousand dollars
D. 250 Thousand dollars
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Suppose gg is a function which has continuous derivatives, and that g(1)=1,g′(1)=5, g″(1)=4, g‴(1)=2
(a) What is the Taylor polynomial of degree 2
for g near 1?
P2(x)=
(b) What is the Taylor polynomial of degree 3
for g near 1?
P3(x)=
(c) Use the two polynomials that you found in
parts (a) and (b) to approximate g(1.1).
With P2, g(1.1)≈
With P3, g(1.1)≈
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Let r(t) = 2t ,4t2 ,2t be a position function for some object.
(a) (2 pts) Find the position of the object at t = 1. (b) (6 pts) Find the velocity of the object at t = 1.
(c) (6 pts) Find the acceleration of the object at t = 1. (d) (6 pts) Find the speed of the object at t = 1.
(e) (15 pts) Find the curvature K of the graph C determined by r(t) when t = 1.
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A firm has monthly average costs, in dollars, given by
C =
42,000 |
x |
+ 200 + x
where x is the number of units produced per month. The
firm can sell its product in a competitive market for $1800 per
unit. If production is limited to 400 units per month, find the
number of units that gives maximum profit.
x = units
Find the maximum profit.
$
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Please answer all 3 questions and explain . thank you.
(1) Determine the length of the curve y= 3 + 2x^(3/2) for 0 ≤ x ≤ 2. You can use your calculator at the last step (after the integration) to determine the approximate length, or you may keep it exact.
(2) Set up, but do not evaluate an integral for the surface area obtained by rotating the curve y = x^3+ 4, 1 ≤ x ≤ 5 (a) about the x-axis. (b)about the y-axis.
(3)Find the particular solution to the differential equation dy dx = y 2 sin x that satisfies the initial condition y(0) = 3.
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Use a triple integral to find the volume of the solid enclosed by the paraboloids y= x2+z2 and y= x2+z2
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The demand for nurses in the US between 2000 and 2015 is estimated to be D(t) = 0.7t 2 + 0.265t + 2000 thousand, where 0 ≤ t ≤ 15, and t = 0 corresponds to year 2000. The number of nurses in the US between 2000 and 2015 is estimated to be S(t) = 0.14t 2 + 0.326t + 1900 thousand, where 0 ≤ t ≤ 15, and t = 0 corresponds to year 2000.
In the marginal analysis, you would use q'(8) to estimate what quantity? Find the exact value of that quantity, and compare with q' (8).
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If all proper nontrivial subgroups of a nontrivial group are isomorphic to each other, must G be cyclic?
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1. Find absolute max and min of f(x,y)= x^2- xy + y^2 +1 on the closed triangular plate in the first quadrant x=0, y=4, y=x
2. Given position of a particle by π (t)= Cos2ti + 3 sin2ti, Find the particle velocity and acceleration at t=0
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1. a) Based on recent statistics, Green Way Airlines expects 4.2% of its customers will be “no shows”. If the airline sold 260 seats for a flight, how many people would the airline expect as “no-shows”? (Round to the nearest whole number)
b) If the airplane can hold 254 passengers, can all those who show up at the gate get on the plane? Explain
2. JK Builders bought 35 acres of land for a housing development. They will give 1.75 acres to the city for a playground and subdivide the remaining land into house lots of 0.875 acres. How many house lots can be formed?
3. The average snowfall amounts for 5 winter months in Burlington, Vermont are given in the table.
a) Find the mean snowfall amount.
b) Find the median snowfall amount.
Month |
Snowfall (in.) |
November |
6.6 |
December |
18.1 |
January |
18.8 |
February |
16.8 |
March |
12.4 |
4. Volunteers from Habitat for Humanity are painting 16 interior walls in new homes that have been built. Each wall measures 14 feet by 6 2/3 feet.
a) If a gallon of paint covers 400 square feet, how many
gallons will be required to paint all the walls? (Round to next
whole number)
b) If each gallon costs $27.95, find the cost of the project.
5. In a recent year, wind machines in the United States generated 17.8 billion kilowatt-hours of electricity (enough to power more than 1.6 million households). The nation’s total electricity production was 4450 billion kilowatt-hours. What percent of the total electrical energy production was generated by wind machines?
6. If a 5 1/4 inch line on a map represents a 9-mile road, how many miles would be represented by a 3 1/2 inch line?
7. At a fire sale, items are being sold at 3/4 off the marked price. What is the sale price of an item that has a marked price of $156?
8. Sixteen ounces of mouthwash costs $3.49 while a 33-ounce container of the same brand costs $6.99. Which is a better buy? Why?
9. The price of gasoline jumped from $3.24 per gallon to $4.05 per gallon in one year. What was the percent increase?
10. You buy 2.75 yards of material at $4.80 per yard and pay $0.87 sales tax. What is the total cost for your purchase?
11. Ruth orders clothes from a retail catalog. She orders two turtleneck tops for $35 each, two pairs of stretch pants for $45 each, one winter jacket for $130, and three leather belts for $25 each. The shipping and handling charge for the order is $15. What is the total charge for Ruth’s order?
12. A recipe for a wedding punch calls for 12 quarts of champagne. If the champagne comes in bottles that are 4/5 of a quart, how many bottles of champagne would be needed?
13. One bank offers a 4-year car loan at an annual simple interest rate of 7% plus a loan application fee of $45. A second bank offers 4-year car loans at an annual simple interest rate of 8% but no loan application fee. If you need to borrow $5800 to purchase a car, which of the two bank loans has the lesser loan cost? (Assume you keep the car for all 4 years.)
14. In a recent survey of new car buyers, 20 of 63 men said they would prefer to buy a silver car while 16 of 49 women said they would prefer silver.
a) Which group has a stronger preference for silver cars?
b) Explain your answer
15. How many acres are contained in 1 square mile? (1 mile = 5280 ft.; 1 acre = 43,560 sq. ft.)
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