The correct answer is Matter is made up of atoms and has mass.
Answer:
Explanation:
Given
mass of crane 
distance moved 
Since it is moving with a constant velocity therefore net force on it is zero
Tension force=weight
T=mg
Work done by Tension T is



Work done by Gravity will be equal in magnitude but opposite in sign and can be obtained by work energy theorem which states that change in kinetic energy of object is equal to work done by all the forces


Answer : The correct option is, (C) 17 m/s
Explanation :
Formula used :

where,
K.E = kinetic energy = 6.8 J
m = mass of object = 46 g = 0.046 kg (1 kg = 1000 g)
v = velocity
Now put all the given values in the above formula, we get:




Therefore, the ball's velocity be as it leaves the cannon is, 17 m/s