(Multiple Choice Worth 5 points) (07.01 MC)

The amount of radioactive uranium changes with time. The table below shows the amount of radioactive uranium f(t) left after time t:

t(hours) 0 0.5 1
f(t) 100 50 25

Which exponential function best represents the relationship between f(t) and t?
f(t) = 100(0.25)t
f(t) = 0.25(100)t
f(t) = 100 (1)t
f(t) = 0.25(50)t
Question 2(Multiple Choice Worth 5 points)
(07.03 MC)

Given four functions, place them in order of their y-intercept, from highest to lowest.

f(x) g(x) h(x) j(x)
the function f of x equals 4 to the x minus 2 power, plus 2 g(x) = 8(20)x Al is monitoring the
decay of a population
of fungi. It is reducing
in half every four weeks.
The population started
at 5.
x j(x)
0 16
1 8
2 4
3 2
g(x), h(x), j(x), f(x)
h(x), j(x), g(x), f(x)
f(x), g(x), j(x), h(x)
j(x), g(x), h(x), f(x)
Question 3(Multiple Choice Worth 5 points)
(07.02 MC)

A savings account compounds interest, at a rate of 15%, once a year. Elizabeth puts $800 in the account as the principal. How can Elizabeth set up a function to track the amount of money she has?

A(x) = 800(15)x where 15 is the interest rate
A(x) = 800(1 + .15)x where .15 is the interest rate
A(x) = 800(.15)x where .15 is the interest rate
A(x) = 800(1 + 15)x where 15 is the interest rate
Question 4(Multiple Choice Worth 5 points)
(07.01 LC)

For accounting purposes, the value of assets (land, buildings, equipment) in a business are depreciated at a set rate per year. The value, V(t) of $408,000 worth of assets after t years, that depreciate at 18% per year, is given by the formula V(t) = Vo(b)t. What is the value of Vo and b, and when rounded to the nearest cent, what are the assets valued at after 8 years?

Vo = $408,000, b = 0.82, and the value after 8 years is $83,400.95
Vo = $408,000, b = 0.18, and the value after 8 years is $0.45
Vo = $408,000, b = 1.18, and the value after 8 years is $108,543.57
Vo = $408,000, b = 0.82, and the value after 8 years is $73,440.00
Question 5(Multiple Choice Worth 5 points)
(07.03 MC)

Clara is taking a medicine for a common cold. The table below shows the amount of medicine f(t), in mg, that was present in Clara's body after time t:

t (hours) 1 2 3 4 5
f(t) (mg) 236.5 223.73 211.65 200.22 189.41

Heidi was administered 300 mg of the same medicine. The amount of medicine in her body f(t) after time t is shown by the equation below:

f(t) = 300(0.946)t

Which statement best describes the rate at which Clara's and Heidi's bodies eliminated the medicine?
Clara's body eliminated the antibiotic faster than Heidi's body.
Clara's body eliminated the antibiotic at the same rate as Heidi's body.
Clara's body eliminated the antibiotic at half of the rate at which Heidi's body eliminated the antibiotic.
Clara's body eliminated the antibiotic at one-fourth of the rate at which Heidi's body eliminated the antibiotic.