有下列四个命题:①相等的角是对顶角;②两条直线被第三条直线所截,同位角相等;③对顶角相等.其中是假命题的个数有 ( )
A:0个
B:1个
C:2个
D:3个
读亚洲气候分布图,回答下列各题。
设等差数列{an}的前n项和为Sn,已知a1=﹣9,a2+a8=﹣2,当Sn取得最小值时,n=( )
Lucy said she __________ cook meals when she was five.