Answer:
The first one is:
(B) oblique impact.
The second one is:
(B) restitution coefficient
Explanation:
A central impact is when both masses are at the line of the impact. When one or both are at an angle, we have an oblique impact. So, the answer of the first one is (B).
The restitution coefficient is the ratio between the restitution impulse to the deformation impulse is called. So, the answer of the second one is also (B).