正午时分,水平放置的正方形在地面上的投影是( )
A.正方形
B.长方形
C.平行四边形
D.菱形
∵正午时分,水平放置的正方形在地面上的投影是正投影,
∴形成的投影是正方形.
故选:A.
Tom's mother demanded that she ________ everything on time. [ ]
A. would tell
B. tell
C. have told
D. be told
按照通报形式,通报可以分为几类?()
A.5
B.4
C.3
D.2