5 A particle \(P\) is projected with speed \(50 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) at an angle of \(40 ^ { \circ }\) above the horizontal from a point \(O\). For the instant 2.5 s after projection, calculate
- the speed of \(P\),
- the angle between \(O P\) and the horizontal.