3 A particle \(P\) of mass 0.25 kg moves under the action of a single force \(\mathbf { F }\) newtons. At time \(t\) seconds, the velocity of \(P\) is \(\mathbf { v } \mathrm { m } \mathrm { s } ^ { - 1 }\), where $$\mathbf { v } = ( 2 - 4 t ) \mathbf { i } + \left( t ^ { 2 } + 2 t \right) \mathbf { j }$$ When \(t = 0 , P\) is at the point with position vector ( \(2 \mathbf { i } - 4 \mathbf { j }\) ) m with respect to a fixed origin \(O\). When \(t = 3 , P\) is at the point \(A\). Find

1. the momentum of \(P\) when \(t = 3\),
2. the magnitude of \(\mathbf { F }\) when \(t = 3\),
3. the position vector of \(A\).