Use the Formula $i = P r t$ To Reach a Solution for the Following Problem

Multiple Choice

Use the formula $i = P r t$ to reach a solution for the following problem. One month a credit card company charged $29.25 in interest on a balance of $3,900. What annual interest rate is the credit card company charging?

A) 11%
B) 9%
C) 8%
D) 9.5%
E) none of these