You Buy an Oven for $1500 on March 20,2013

Multiple Choice

You buy an oven for $1500 on March 20,2013.The store gives you 4 months "interest free",so on July 20,2013 you must pay the $1500.However,the store charges an administration fee of $75,which must be paid up front when you buy the oven (March 20,2013) .What rate of simple interest,r,are you being charged for this "interest free" plan?

A) 15.79%
B) 14.25%
C) 14.96%
D) 15.75%