Diana bought a stereo for $530, which was the retail price plus a 6 percent sales tax. How much money could she have saved if she had bought the stereo at the same retail price in a neighboring state where she would have paid a sales tax of 5 percent ？（）

单项选择题The markup on a television set is 20 percent of the cost. The markup is what percent of the selling price ？（） (mark up=selling price-cost)

A.A
B.B
C.C
D.D
E.E

单项选择题If it is 6:27 in the evening on a certain day, what time in the morning was it exactly 2,880, 717 minutes earlier ？（） (Assume standard time in one location．)

A.6：22
B.6：24
C.6：27
D.6：30
E.6：32