直放站三阶互调指标的测试,哪个说法是错误的?()
A.在2f1-f2处测量
B.在2f2-f1处测量
C.在(f1+f2)/2处测量
D.A和B
参考答案:D
The lady has devoted much of her time ________ South China tigers. [ ]
A. To protect
B. to protecting
C. Protected
十进制数29的二进制数为()
A.11011
B.11110
C.11101
D.11001