A firework whose mass is 7kg is launched vertically up into the air. After it reaches its the height of 160m, it blasts and splits into two pieces; pieces A and B. The two pieces fly off and travel horizontally. The blasts of the fireworks lasts 10ms. Piece A (mass of 1.50kg ) touches the ground 300 meters away from the launch position

Question

A firework whose mass is 7kg is launched vertically up into the air. After it reaches its the height of 160m, it blasts and splits into two pieces; pieces A and B. The two pieces fly off and travel horizontally. The blasts of the fireworks lasts 10ms. Piece A (mass of 1.50kg ) touches the ground 300 meters away from the launch position 
Determine: 
a) the magnitude of the momentum transferred to A due to explosion 
b) the magnitude of impulse delivered to A by gravity during the explosion 
c) how far B lands from the launch position