I think the answer is periodic motion.
D. convergent plate boundary involving an oceanic plate
Answer:

Explanation:
Mass of the Sun, 
The radius of the Sun, 
We need to find the acceleration due to gravity on the surface of the Sun. It is given by the formula as follows :

So, the value of acceleration due to gravity on the Sun is
.
Answer:
The current is not used up. The electrons flow through the entire circuit and this travel is the current. They flow until they are not charged anymore. That is also why the circuit must be closed or else electrons would escape not just light it up for a second then go out.
Explanation:
Given :
The focal length of a concave mirror is 18 cm.
To Find :
The radius of curvature of the concave mirror.
Solution :
We know,

Therefore, the radius of curvature of concave mirror is 36 cm.
Hence, this is the required solution.