here is the a part
LET B the topmost point of the incline.
Net force on the particle at A and B, F = mgsinA
Work done to reach from point B to C (horizontal position of the circular path on the other side) = mgh
= mgR (1-cosA )
So total work done = mg {lsinA + R (1-cosA)}
Net change in KE = work done
½ mv2 = mg {lsinA+R (1-cosA)}
V = {2g[R (1-cosA) + lsinA]}1/2--------------------ANS
hope u got it.