<span>The time needed for a wave to make one complete cycle is its period.</span>
There are no choices on the list you provided that make such a statement,
and it's difficult to understand what is meant by "the following".
That statement is one way to describe the approach to 'forces of gravity'
taken by the theory of Relativity.
Answer:
The answer is A. on edgen.
Explanation:
A. adding in the boxes an arrow that points from Qh to Qc