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: in a 80 meters race a beats b by 56 m or 7 seconds . a ' s time over the course is : 
Options: a ) 3 seconds , b ) 12 seconds , c ) 10 seconds , d ) 18 seconds , e ) 28 seconds
a

Problem: r is the set of positive even integers less than 20 , and s is the set of the squares of the integers in r . how many elements does the intersection of r and s contain ? 
Options: ['a ) none', 'b ) two', 'c ) three', 'd ) five', 'e ) seven']
c

Problem: in a dairy farm , 26 cows eat 26 bags of husk in 26 days . in how many days one cow will eat one bag of husk ? 
Options: a ) 1 , b ) 40 , c ) 20 , d ) 26 , e ) 30

d