Answer
The equation would be B(t)=500$\times$$2^{t}$
a)
The budget in 1 yr will be 1000
The budget in 2 yrs will be 2000
The budget in y years will be 500$\times$$2^{y}$
b)
The budget 2 years ago was $125
Work Step by Step
The equation would be B(t)=500$\times$$2^{t}$ as the initial budget was 500 and it doubles so a=500 and b=2, which is the growth factor.
a)
The budget in 1 yr
B(1)=500$\times$$2^{1}$ = 500$\times$2 = 1000
The budget in 2 yrs
B(1)=500$\times$$2^{2}$ = 500$\times$4 = 2000
The budget in y years will be 500$\times$$2^{y}$
b)
The budget 2 years ago (t=-2)
B(-2)=500$\times$$2^{-2}$ = $\frac{500}{2^{2}}$ = $\frac{500}{4}$ = $125
