第19题: [单项选择]某地大气环境监测PM10的日平均浓度为0.45mg/m3,环境空气质量标准中PM10二级标准日平均浓度为0.15mg/m3,则超标倍数为()。 A. 1倍 B. 2倍 C. 3倍 D. 4倍 参考答案:B 答案解析:根据已知条件,超标倍数=(0.45-0.15)÷0.15=2倍。
参考答案:far below zero degree/7degrees below zero 答案解析:第一段第—句里“In temperatures of twenty-five degree sbelow zero Fahrenheit...”的意思是“在温度处于华氏零下25度时”。华氏冰点为32度
第33题: [单项选择](Even though) he (had been studying) English for three years (before) he came to England, it is still difficult for him to make himself (understand). A. Even though B. had been studying C. before D. understand 参考答案:D