I believe the answer would be C.
The energy would remain equal to that of the initial kinetic energy since it is a frictionless surface. However if it is an inelastic collision then energy would be lost due to sound and heat.
The highest tides and rarest whales on earth
Explanation:
(1) We have,
Wavelength of a wave is 2 meters
Frequency of a wave is 6 Hz
It is required to find the velocity of a wave. The velocity of a wave is given by :
So, the velocity of a wave is 12 m/s.
(2)
Number of waves passing are 100
Time taken to pass the wave is 5 seconds
The frequency of wave is given by total number of waves passing per unit time. So,

Frequency of a wave is 20 Hz.
When mass is doubled, KE is doubled.
When speed is doubled, KE becomes 4 times as great.
When both are doubled (last choice), KE is multiplied by 8 .