1.A fruit fly population of 182 flies is in a closed container. The number of flies grows exponentially, reaching 340 in 18 days. Find the doubling time (time for the population to double) to the nearest tenth of a day.

19.9 days

20.0 days

18.0 days

2.0 days

2.One thousand dollars is invested at 5% continuous annual interest. This means the value of the investment will grow exponentially, withkequaling the decimal rate of interest. What will the value of the investment be after 7 1/2 years?

$1,375.00

$375.00

$1,454.99

$454.99

3.A population grows exponentially, doubling in 4 hours. How long, to the nearest tenth of an hour, will it take the population to triple?

8.0 hours

10.3 hours

6.3 hours

6.6 hours

4.The half-life of a newly discovered radioactive element is 30 seconds. To the nearest tenth of a second, how long will it take for a sample of 9 grams to decay to 0.72 grams?

109.3 seconds

42.5 seconds

30.8 seconds

99.7 seconds

5.

Find the particular solution toy dx = x dygiven thaty(8) = 2.

x= 4y

y= 4y

ln|x|=ln|y|+ln6

ln|x|=ln|y|+ln4

6.Which of the following is a first-order homogeneous differential equation?

dy/dx = (3x^3-2x^2y)/xy^2

dy/dx=(x^2y^3 - y^5)/(2xy^5)

dy/dx=(5xy-5y-5x)/y

none