(A)>5 (B)>2 (C)>4 (D)<5
(A)380V(-10%~15%) (B)280V(-10%~15%) (C)300V(-15%~10%) (D)220V(-15%~10%)
(A)地中衡 (B)地上衡 (C)材料衡 (D)靜態(tài)衡