instruction:
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'.
question:
Problem: two taps a and b can fill a cistern in 12 minutes and 18 minutes respectively . they are turned on at the same time . if the tap a is turned off after 4 minutes , how long will tap b take to fill the rest of the cistern ? 
Options: a ) 8 min . , b ) 9 min . , c ) 10 min . , d ) 7 min . , e ) none of these
answer:
a


question:
Problem: two trains of equal lengths take 10 sec and 8 sec respectively to cross a telegraph post . if the length of each train be 120 m , in what time will they cross other travelling in opposite direction ? 
Options: a ) 22 , b ) 12 , c ) 9 , d ) 99 , e ) 21
answer:
c


question:
Problem: 15 girls can complete a rangoli in 12 days , and 10 boys can complete the same work in 15 days . to complete the work earlier 10 boys and 15 girls are employed , in how many days will this work get completed ? 
Options: a ) 6 , b ) 7 , c ) 6.5 , d ) 6 2 / 3 , e ) 6 1 / 4
answer:

d