A.对
B.错
A.(x,y)=(16,13),d=9
B.(x,y)=(16,12),d=9
C.(x,y)=(16,13),d=-21
D.(x,y)=(16,12),d=-21
A.增加端点P0/=2P0-P1,Pn/=2Pn-Pn-1
B.将原端点替换为P0/=2P0-P1,Pn/=2Pn-Pn-1
C.增加端点P0/=P0-2P1,Pn/=Pn-2Pn-1
D.将原端点替换为P0/=P0-2P1,Pn/=Pn-2Pn-1
A.必须简明清晰,易于辨认
B. 涂刷、拴挂、粘贴标记和标志的部位要适当
C. 要选用明显的颜色作标记和标志
D. 标记和标志的规格尺寸要统一