let velocity of ball (solid sphere) just after collision be 'u' m/s
u = ev0.................(i)
just after collision the ball will have 'u' in opposite to the direction of initial motion & angular velocity in same direction to that of initial motion
as wall is smooth, there is no loss in energy due to friction,
let 'v' be the velocity of the ball when it starts pure rolling in opposite dir.
friction = ma
=> 
equation of torque..
mar = (0.4)mr2@ (@ = ang. acc)
a = 0.4r@........(ii)
equation of motion
v = u - at ...........(iii)
v/r = -v0/r + @t..............(iv) ( t = time after which ball starts pure rolling after collision)
from (ii),(iii),(iv) eleminating 't'
7v = 5u - 2v0
from (i)

substituting the values,
v = 1.5 m/s
PLEASE RATE.......