冷饮食品的主要卫生问题是
A.真菌毒素、多环芳烃、棉酚B.甲醇、杂醇油、醛类C.重金属污染D.微生物、有害化学物质污染E.亚硝基化合物污染
参考答案:D
---Could you tell me what time the train leaves Hefei for Beijing?
---I’m afraid you need to ______on the Internet.
A.look for it
B.look at it
C.look it over
D.look it up
煤矿井下远距离控制线路的额定电压不超过24V()