______the fight stopped, travel across the country has been quite safe.
A. Since
B. When
C. After
D. Unless
查看答案
They were just about to leave _______the telephone rang.
A. before
B. when
C. as
D. than
一个具有 A、 B、 C 三个逻辑变量的逻辑函数 Y=AB+AC+BC 是它们的最小项表达式。
A. 对
B. 错
逻辑函数与真值表之间没有关系。
A. 对
B. 错