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'.

[EX Q]: Problem: a cyclist bikes x distance at 8 miles per hour and returns over the same path at 10 miles per hour . what is the cyclist ' s average rate for the round trip in miles per hour ? 
Options: a ) 8.1 , b ) 8.9 , c ) 8.6 , d ) 8.3 , e ) 9.0
[EX A]: b

[EX Q]: Problem: a tree is 12 m tall and casts an an 8 m long shadow . at the same time , a flag pole caste a 100 m long shadow . how long is the flag pole ? 
Options: a ) 150 m , b ) 200 m , c ) 125 m , d ) 115 m , e ) none
[EX A]: a

[EX Q]: Problem: a courtyard is 20 meter long and 16 meter board is to be paved with bricks of dimensions 20 cm by 10 cm . the total number of bricks required is ? 
Options: a ) 16000 , b ) 27778 , c ) 20000 , d ) 27999 , e ) 17799
[EX A]:
a