In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: the length of the bridge , which a train 140 metres long and travelling at 45 km / hr can cross in 30 seconds , is : 
Options: a ) 200 m , b ) 235 m , c ) 245 m , d ) 250 m , e ) 270 m

Answer: b


Question: 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 36 miles per hour . how many miles from the station was train a overtaken by train b ? 
Options: a ) 320 , b ) 360 , c ) 400 , d ) 440 , e ) 480

Answer: b


Question: Problem: three pipes a , b and c can fill a tank from empty to full in 20 minutes , 20 minutes and 30 minutes respectively . when the tank is empty , all the three pipes are opened . a , b and c discharge chemical solutions p , q and r respectively . what is the proportion of solution r in the liquid in the tank after 3 minutes ? 
Options: a ) 1 / 2 , b ) 1 / 5 , c ) 1 / 3 , d ) 1 / 4 , e ) 1 / 6

Answer:
d