Gmat DS 求解

Gmat DS 求解
If the length of Wanda's telephone call was rounded up to the nearest whole minute by her telephone company, then Wanda was charged for how many minutes for her telephone call?
　　(1) The total charge for Wanda's telephone call was $6.50.
　　(2) Wanda was charged $0.50 more for the first minute of the telephone call than for each minute after the first.
A.Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B.Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C.BOTH statement TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D.EACH statement ALONE is sufficient.
E.Statements (1) and (2) TOGETHER are NOT sufficient.
我不理解题目导致做不来,求讲解啊~