Detailed Instructions: 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'.
Q: Problem: if 20 men can build a wall 66 metres long in 10 days , what length of a similar can be built by 86 men in 8 days ?
Options: a ) 227.04 mtrs , b ) 378.4 mtrs , c ) 478.4 mtrs , d ) 488.4 mtrs , e ) 578.4 mtrs
A:
a