题干
The new technology, if _________ to rice growing, will help increase the grain output．
A：applied
B：applying
C：to apply
D：having applied
答案(点此获取答案解析）
A
The new technology, if _________ to rice growing, will help increase the grain output．
A：applied
B：applying
C：to apply
D：having applied
，E为侧棱PC的中点，则PA与BE所成的角为（ ）