Quantitative Reasoning

If an express elevator rose from the ground floor to the top floor of a building in 120 seconds, how many seconds did it take to return to the ground floor?

(1) The distance from the ground floor to the top floor is 1,200 feet.

(2) The ascending speed is 7/8 of the descending speed.

Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
EITHER statement BY ITSELF is sufficient to answer the question.
Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.

The answer was given to me including the solution but I still can't seem to understand. If anybody can help break down the explanation for me in lament terms that would be helpful. Thanks!