In our class there are 45 ________.( )
A:a pupil
B:pupils
C:pupil
(II)把b绕O点逆时针旋转90°.
(III)把图c按3:1的比放大.
在y=□x2□4x□4的□中,任意填上“+”或“﹣”,可组成若干个不同的二次函数,其中其图象与x轴只有一个交点的概率是( )
After the long trip, we all feel ________. We need to have a rest.