A.10V B.-10V C.2.63% D.-2.63%
A.3% B.5% C.7% D.10%
A.一級(jí)負(fù)荷 B.二級(jí)負(fù)荷 C.三級(jí)負(fù)荷 D.四級(jí)負(fù)荷