In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: cost is expressed by the formula tb ^ 4 . if b is doubled , the new cost is what percent of the original cost ? 
Options: a ) 200 , b ) 600 , c ) 800 , d ) 1600 , e ) 50

Answer: d


Question: Problem: if - 3 x + 2 y = 28 and 3 x + 6 y = 84 , what is the product of x and y ? 
Options: a ) 264 . , b ) 428 , c ) 0 , d ) 462 , e ) 642

Answer: c


Question: Problem: two heavily loaded sixteen - wheeler transport trucks are 787 kilometers apart , sitting at two rest stops on opposite sides of the same highway . driver a begins heading down the highway driving at an average speed of 90 kilometers per hour . exactly one hour later , driver b starts down the highway toward driver a , maintaining an average speed of 80 kilometers per hour . how many kilometers farther than driver b , will driver a have driven when they meet and pass each other on the highway ? 
Options: a ) 90 , b ) 131 , c ) 150 , d ) 320 , e ) 450

Answer:
b