I believe it’s 60km/h
I divided the total distance (120 km) by the time it took to get there (2h) to get this.
Answer:
The gain in velocity is 0.37m/s
Explanation:
We need solve this problem though the conservation of momentum. That is,


Using the equation to find
,

Using the conservation of energy equation, we have,




Now this energy over the cannonball



The gain in velocity is 0.37m/s
Single replacement would be represented by a single element being replaced.
This is shown in answer choice B
Where the positions of A and B are swapped
Answer: The magnitude of impulse imparted to the ball by the golf club is 2.2 N seconds
Explanation:
Force applied on the golf ball = 
Mass of the ball = 0.05 kg
Velocity with which ball is accelerating = 44 m/s
Time period over which forece applied = t


Newton seconds
The magnitude of impulse imparted to the ball by the golf club is 2.2 N seconds
B) It’s material moves due to convection currents.