Sam covers a total distance of \(80\text{ km}\) while travelling from a certain point \(X\) to a certain point \(Y\) and come back again to the start point \(X.\) He covers the first \(40 \text{ km}\) distance from point \(X\) to point \(Y\) at a speed of \(25 \text{km/hr}.\) While travelling back to the point \(X\) from point \(Y,\) Sam drives his vehicle at a speed of \(15 \text{ km/hr}.\) Calculate the average speed of Sam for the entire journey.

A. \(20.77 \text{ km/hr}\)
B. \(18.77 \text{ km/hr}\)
C. \(35.77 \text{ km/hr}\)
D. \(17.77 \text{ km/hr}\)
E. None of the above

The OA is B