A:You must take charge of it.
B:Wait for your punishment.
C:I’d like a refund, please.
D:I won’t agree with that.
已知a1,a2,…a2002均为正数,且满足M=(a1+a2+…+a2001)(a2+a3+…+a2001-a2002),N=(a1+a2+…+a2001-a2002) (a2+a3+…+a2001),则M与N之间的关系是( )
圆形的操场的一周全长是1800米.如果沿着这一圈每隔12米安装一盏灯,一共需要装几盏灯?