Answer:
f(t) = 1.22·(173/122)^(t/5)
Step-by-step explanation:
(a) An exponential growth (or decay) function can be written using the form ...
f(t) = (initial value)·(ratio in period)^(t/period)
Here, we're given an initial value of 1.22, a growth ratio of 1.73/1.22 in a period of 5 years, so we can write the function as ...
f(t) = 1.22·(173/122)^(t/5)
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(b) In 2038-2012 = 26 years, the value of the function is ...
f(26) = 1.22·(173/122)^(26/5) ≈ 7.50 . . . . million
