3 A particle \(A\) is released from rest from the top of a smooth plane, which makes an angle of \(30 ^ { \circ }\) with the horizontal. The particle \(A\) collides 2 s later with a particle \(B\), which is moving up a line of greatest slope of the plane. The coefficient of restitution between the particles is 0.4 and the speed of \(B\) immediately before the collision is \(2 \mathrm {~m} \mathrm {~s} ^ { - 1 } . B\) has velocity \(1 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) down the plane immediately after the collision. Find

1. the speed of \(A\) immediately after the collision,
2. the distance \(A\) moves up the plane after the collision. The masses of \(A\) and \(B\) are 0.5 kg and \(m \mathrm {~kg}\), respectively.
3. Find the value of \(m\).