若正方形的周长为40,则其对角线长为( )
A:100
B:202
C:102
D:10
_________ name is Amy.
①发明指南针 ②造纸技术 ③烧制陶瓷 ④火药的发明 ⑤青铜器的制造.
— Is she your ____ (mother, sister)?
— Yes. She is.