4 The growth of a population of bacteria can be modeled by an exponential function. The graph models
the population of the bacteria colony Pt) as a function of the time , in weeks, that has passed.
ΤΡΟ
P(t) = 500(2)
18000
16000
14000
12000
10000
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Part A) What is the y-intercept of the function? What does it represent in this context?
Part B) Which of the following statements most appropriately describes the domain of this function in
this situation?
A. The domain is the real numbers greater than 500. The domain represents the time, in weeks,
that has passed.
B. The domain is the real numbers greater than 500. The domain represents the population of the
colony after a given number of weeks.
c. The domain is the nonnegative real numbers. The domain represents the time, in weeks, that
has passed.
D. The domain is the nonnegative real numbers. The domain represents the population of the
colony after a given number of weeks.