To my delight, I ____ from hundreds of applicants to attend the opening ceremony.
A:was chosen
B:was being chosen
C:would choose
D:had chosen
cháo zhe
chì bǎnɡ
bí zi
liè rén
wù ménɡ ménɡ
dǒu dònɡ
____
气候最主要的两大要素是( )
(Ⅰ)求证:AB∥EF;
(Ⅱ)若PA=PD=AD,且平面PAD⊥平面ABCD,求平面PAF与平面AFE所成的锐二面角的余弦值.
450毫升=____立方厘米