algebra question

Question

Suppose that the dollar value v(t)

 of a certain car that is t years old is given by the following exponential function.

v(t)=22,800(0.81)^t

1.find initial value of car

2.does the function represent growth or decay

3.By what percent does the value of the car change each year?

Answer 1

1. $22,800
2. decay
3. 19 per cent