Task: Question Answering
Input (English): Problem: for any positive integer n , the sum of the first n positive integers equals n ( n + 1 ) / 2 . what is the sum of all the even integers between 99 and 161 ? 
Options: a ) 2670 , b ) 2980 , c ) 3550 , d ) 4030 , e ) 4540
Output (English): d