To get the exponential model we use the form:
y=abˣ
where:
a=initial value
b=growth factor
y=number of years
thus using point (1,63) and (2,226)
the growth factor will be:
b=(226/63)=3.587~3.6
a=63
thus the formula for the function will be:
A(y)=a(3.6)^y
substituting (1,63) in the equation and solving for a.
63=a(3.6)^1
thus
a=63/3.6=17.5
hence the formula will be:
A(y)=17.82(3.6)^y
Answer: D] 17.5(3.6)^y
2] The number of acres defoliated after 5 years will be as follows:
y=5 years
A(y)=17.82(3.6)^y
plugging in the value we get:
A(y)=17.82(3.6)^5
simplifying the above
A(y)=10775.07
A(y)=10775
Answer: D