问题
单项选择题
图示非周期信号u(t)的时域描述形式是()(注:1(t)是单位阶跃函数)
A.
B.
C.
D.
答案
参考答案:B
图示非周期信号u(t)的时域描述形式是()(注:1(t)是单位阶跃函数)
A.
B.
C.
D.
参考答案:B
A. poster from a club B. note to parents C. poster from a supermarket 小题2:Mr. White will take her 5-year-old son to see a film in the club. She hopes the film will be over before 1 p.m.. So they should go to the club on________. A. April 2 B. April 9 C. March 19 小题3:________ can go to the cinema in the club alone. A. A 2- year-old baby B. A 14- year-old student C. A 20- year-old parent 小题4: The film ________ is the longest. A. Two Brothers B. Mr. Bean’s Holiday C. Meet the Robinsons 小题5: Parents could collect their children in the cinema ________. at any time at the start of the film at the end of the film |