47. A swimming pool of uniform depth is being filled. When the pool started filling, its drain was closed. The graph below shows the depth of the water in the pool as a function of the length of time that water has been flowing into the pool.
Exactly 1 event occurred at time a that changed the rate at which the depth was increasing. Which of the following could have been that event?
I. The flow of water into the poo] was increased.
II. The flow of water into the pool was decreased.
III. The drain was opened.
Your Answer is
Correct Answer is E
Explanation
It can be seen from the figure that after time a, the growth rate of water depth slows down. So again it could be that the water is getting in slower, or it could be that the drainage system is open, but it can't be that the water is getting in faster.