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: a can do a piece of work in 4 hours ; b and c together can do it in 2 hours , while a and c together can do it in 2 hours . how long will b alone take to do it ? 
Options: a ) 12 , b ) 9 , c ) 8 , d ) 6 , e ) 4
answer:
e


question:
Problem: raja complete a journey in 10 hours . he travels first half of the journey at the rate of 21 km / hr and second half at the rate of 24 km / hr . find the total journey in km . 
Options: a ) 200 km , b ) 250 km , c ) 224 km , d ) 255 km , e ) 260 km
answer:
c


question:
Problem: the reciprocal of the hcf and lcm of two are 1 / 17 and 1 / 312 . if one of the number is 24 then other no . is 
Options: a ) 126 , b ) 136 , c ) 146 , d ) 221 , e ) 266
answer:

d