A:I had breakfast seven times last week.
B:I had breakfast five times last week.
C:I had breakfast once last week.
下列图形中对称轴最多的是( )
如图,OA=4,线段OA的中点为B,点P在以O为圆心,OB为半径的圆上运动,PA的中点为Q.当点Q也落在⊙O上时,cos∠OQB的值等于( )
下列各句中,划线的成语使用恰当的一句是( )
Lily isn't as ________ as Peter. She often makes mistakes in her composition.
决定闭合电路中感应电动势大小的因素是( )