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 35 miles per hour . how many miles from the station was train a overtaken by train b ? 
Options: a ) 420 , b ) 450 , c ) 480 , d ) 510 , e ) 540
Output (English): a