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'.

Problem: kathleen can paint a room in 2 hours , and anthony can paint an identical room in 7 hours . how many hours would it take kathleen and anthony to paint both rooms if they work together at their respective rates ? 
Options: a ) 28 / 9 , b ) 4 / 3 , c ) 15 / 8 , d ) 9 / 4 , e ) 15 / 4
a

Problem: 13 buckets of water fill a tank when the capacity of each bucket is 51 litres . how many buckets will be needed to fill the same tank , if the capacity of each bucket is 17 litres ? 
Options: a ) 39 , b ) 28 , c ) 23 , d ) 12 , e ) 24
a

Problem: if 15 men can reap 80 hectares in 24 days , then how many hectares can 36 men reap in 30 days ? 
Options: a ) 127 , b ) 240 , c ) 287 , d ) 450 , e ) 281

b