A.60° B.90° C.120° D.180°
A.電能轉(zhuǎn)化為化學(xué)能 B.電能轉(zhuǎn)化為熱能 C.化學(xué)能轉(zhuǎn)化為電能 D.熱能轉(zhuǎn)化為化學(xué)能
A.1 B.1.5 C.2 D.2.5