A:five dozens; one doze
B:five dozens of; one dozen of
C:five dozen ; one doze
D:dozens of ; one dozen of
设计算法,输出1000以内能被3和5整除的所有正整数,已知算法流程图如图,请填写空余部分:①____;②____ .
已知实数x,y满足2x+y-2≥0x-2y+4≥03x-y-3≤0,则x2+y2的最大值为____ .