不定项选择
A.3500+120+80-(1400-60)-17.5- 125-400-30-100+120+80 B.3500+120+80-(1400-60)-20-125- 400-30-(100-40)+120+80 C.3500+120+80-(1400-60)-21-125- 400-30-(100-40)+40+120+80 D.3500+120+80-(1400-60)-13.5- 125-400-30-(100-40)+120+80
A.5200 B.2300 C.4100 D.4500
A.12 B.18 C.36 D.40