What’s the initial value and value after 13 years

we have given cost function which is exponential [tex] v(t)=20000(0.86)^t [/tex].
we need to find the cost of a car at time t initially and after 13 years .
we need to plug t=0 and t=13 in v(t).
[tex] v(0)=20000(0.86)^0=$20000 [/tex].
and [tex] v(13)=20000(0.86)^(13)=$2815.20 [/tex].
so the value of car is initially $20000 and after 13 years it was $2815.20.