I've done 3 and 4 just want a clarification that its right
Q3) Maxim, of mass 70kg, is running at 3.5ms-1 when he jumps on a skateboard, of mass 2.2kg, travelling at 0.8 ms-1 in the same direction.
i. Calculate their new combined velocity.
Q4) Maxim is on his skateboard again travelling at...