Answer:
-0.5%
Explanation:
Given :A motorcycle cost $12,000 when it was purchased.
The value of a motorcycle decreases by 6% each year.
To Find : Find the rate of decay each month
Solution :
Rate of decay per yer = 6%
Rate of decay in 12 months = 6%
Rate of decay in 1 month =

=
So, Rate of decay each month is -0.5%
Hence Option D is true .