<h2>Explanation:</h2><h2></h2>
Hello! Remember you have to write complete questions in order to get good and exact answers. I'll help you to understand this problem, but I have to assume some things.
We know that the empty cup in the shape of a cylinder is being filled with water. Suppose the volume of this cylinder is:
Suppose that the cup is filled at a constant rate of , so in 7 seconds the cup is filled the following amount:
So this represents the following percentage:
Finally, after 7 seconds the cup is 77.78% filled