Answer:
Deflation
Explanation:
The process by which wind removes surface materials is called deflation.
Deflation is a process by which wind erodes the Earth's exterior and the regions which experience severe erosion are called deflation zones.
deflation originates by the erosive force of a wind that removes the loosened area and this process is facilitated by a dry climate and a loss of vegetative cover that helps to lose the sediment.
deflation is common in the arid regions.
Answer:
c. 
Explanation:
= Initial distance between asteroid and rock = 7514 km = 7514000 m
= Final distance between asteroid and rock = 2823 km = 2823000 m
= Initial speed of rock = 136 ms⁻¹
= Final speed of rock = 392 ms⁻¹
= mass of the rock
= mass of the asteroid
Using conservation of energy
Initial Kinetic energy of rock + Initial gravitational potential energy = Final Kinetic energy of rock + Final gravitational potential energy

The magnitude is doubled. The direction doesn't change.
To solve this problem divide 60 by 4.6
The answer to this problem is 13 seconds.