The speed of train increase at a constant rate alpha from zero to v then remain constant for an interval and finally decreases to zero at rate of Betha if let l be total distance travelled then time taken to travel is a) l/v+v/2(1/α+1/β) b) l/v+2/v(1/α+1/β) c) l/v+2v(1/α+1/β) d) l/v+1/v(1/α+1/β)
