ere are some problems that I am having issues solving. Any help is appreciated.

Part 3: Apply what you know about integrals to answer.

14. The average credit card debt per U.S. household between 1990 and 2003 was growing at the rate of approximately

D(t)= -4.479t^2 + 69.8t + 279.5 (0 ≤ t ≤ 13)

dollars/year. The average credit card debt per U.S. household stood at $2917 in 1990.

a) Let t = 0 correspond to the year 1990. Write an expression that would give the approximate average credit card debt per U.S. household in year t.

b) Use your expression from part a) to estimate the average credit card debt per U.S. household in 2003.

15. Annual sales (in millions of units) of pocket computers are expected to grow in accordance with the function

f(t)=0.18t^2 + 16t +2.64 (0 ≤ t ≤ 6)

where t is measured in years, with t = 0 corresponding to 1997.

a) How many computers were sold over the 6-year period between the beginning of 1997 and the end of 2002?

b) How many computers were sold during the year 2000?

16. Suppose in a certain country the life expectancy at birth of a female is changing at the rate of

g'(t)= 5.45218 / (1 + 1.09t)^0.9

Years/year. Here, t is measured in years, with t = 0 corresponding to the year 1900. Find an expression giving the life expectancy at birth (in years) of a female in that country if the life expectancy at the beginning of 1900 is 50 years. What is the life expectancy at birth of a female born in 2000 in that country?

17. A car moves along a straight road in such a way that its velocity (in feet/second) at any time t (in seconds) is given by

v(t) = 3t*sqrt(16-t^2) (0 ≤ t ≤ 4)

Find the distance traveled by the car in the 4 seconds from t = 0 to t = 4.

## Desperately Need Help With Integralsl ! Help!?

March 12th, 2015 admin