Task: Question Answering
Input (English): Problem: train a leaves the station traveling at 30 miles per hour . two hours later train в leaves the same station traveling in the same direction at 45 miles per hour . how many miles from the station was train a overtaken by train b ? 
Options: a ) 100 , b ) 120 , c ) 140 , d ) 160 , e ) 180
Output (English): e