SQL语句中,彻底删除一个表的命令是()。
A、delete
B、drop
C、clear
D、remore
参考答案:B
补全对话。
A: Nice to you, Sally.
B: Nice to meet you, .
A: do you get up everyday?
B: At about 6:00.
A: When do you to school?
B: At 7 :00.
A: When you go home?
B: 5:00.
A: When do you go to ?
B: At 9:00 the evening.
A: Thank you telling me.
B: You're .
用万用表测二极管正反向电阻,若()时,此管可以使用。
A.正、反向电阻相差很大
B.正、反向电阻相差不大
C.正、反向电阻都很小
D.正、反向电阻都很大