[单项选择]According to the researchers, cream sours faster than butter because bacteria ______ A. are mom evenly distributed in cream B. multiply more easily in cream than in butter C. live on less fat in cream than in butter D. produce less waste in cream than in butter.
参考答案:B 答案解析:根据第三段的"The bacteria which make the food go bad prefer to live in the watery regions of the mixture
第30题: [单项选择]ZR-KVVP2450/750V的全称() A. 450/750v铜芯聚氯乙烯绝缘聚氯乙烯护套铜带屏蔽阻燃控制电缆 B. 450/750v铜芯聚氯乙烯绝缘聚氯乙烯护套编织屏蔽阻燃控制电缆 C. 450/750v铜芯聚氯乙烯绝缘聚氯乙烯护套铝塑复合带屏蔽阻燃控制电缆 D. 450/750v铜芯聚氯乙烯绝缘聚氯乙烯护套控制电缆 参考答案:A