Task: Question Answering
Input (English): Problem: a vendor sells 50 percent of the apples he had and throws away 20 percent of the remainder . the next day , the vendor sells 50 percent of the remaining apples and throws away the rest . in total , what percent of his apples does the vendor throw away ? 
Options: a ) 30 , b ) 35 , c ) 40 , d ) 45 , e ) 50
Output (English): a