Task: Question Answering
Input (English): Problem: the mall charges 40 cents for the first hour of parking and $ 3 for each additional hour until the customer reaches 4 hours , after that the parking fee is $ 2 per hour . if mr . park parked his car in the mall for 7 hours and 30 minutes , how much is he going to pay ? 
Options: a ) $ 6.8 , b ) $ 12 . , c ) $ 13 . , d ) $ 14.5 . , e ) $ 15 .
Output (English): a