Task: Question Answering
Input (English): Problem: if it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 750 responses are needed , what is the minimum number of questionnaires that should be mailed ? 
Options: a ) 1160 , b ) 1190 , c ) 1220 , d ) 1250 , e ) 1280
Output (English): d