【单选题】下列命题中,正确的是
B.
命题“ 为真”是命题“ 为真”的必要不充分条件
【简答题】Which sign can you probably see in the supermarket? A. B. C. D.
【单选题】Which sign can you probably see in the library?
【单选题】Which sign means you can't turn left? [ ]
【单选题】Which sign can you mostly see in the school library?
【单选题】下列命题中,正确的是
C.
命题“ 为真”是命题“ 为真”的必要不充分条件
【简答题】下列命题中不正确的为 A上升气速过大会引起漏液 B 上升气速过大会引起液泛 C上升气速过大会使塔板效率下降 D 上升
【单选题】— Which sign can't be seen on the road? — _____. [ ]