If we are to derive the equation that models the growth of the amoeba, we make use of the general form:
p = po k^t
where po is the initial population
k is the multiplicative rate of change
From the problem
3po = po k^(20)
k = 1.06
The equation is
p = 800 (1.06)^t
plug a=2 and b=4 in the expression
5(2)+7(4)
simplify
10+28
solve
=38
116 is the answer hope it helps!
Dilation because the change of size