数字式电压表的测量速率取决于()
A.时钟脉冲的频率
B.基准电压的高低
C.电源电压的高低
D.电源电压的频率
参考答案:A
—I read a story about the film star.
—Who it? [ ]
A. writes
B. wrote
C. is writing
D. is going to write