A.熱電勢(shì)輸出不穩(wěn)定 B.熱電勢(shì)比實(shí)際值大 C.熱電勢(shì)比實(shí)際值小 D.熱電勢(shì)無(wú)變化
A.C—A—B B.A—B—C C.B—C—A D.A—C—B