Task: Question Answering
Input (English): Problem: the temperature of a certain cup of coffee 10 minutes after it was poured was 120 degrees fahrenheit . if the temperature f of the coffee t minutes after it was poured can be determined by the formula f = 120 ( 2 ^ - at ) + 60 , where f is in degrees fahrenheit and a is a constant . then the temperature of the coffee 80 minutes after it was poured was how many degrees fahrenheit ? 
Options: a ) 45 , b ) 56 , c ) 60.4 , d ) 85 , e ) 90
Output (English): c