第24题: [单项选择]The suggested causes of a given phenomenon cannot always be independently observed, and so it is hard to ______ the possibility of there being explanations alternative to the one proposed. A. account for B. rule out C. guard against D. do with 参考答案:B 答案解析:account for解释；guard against防备；do with可以用have/be to do with something“与某事有关”；上述三项，均与题义不符。rule out“排除…
第31题: [单项选择]A级洁净工作区中，≥5μm动态悬浮粒子最大允许数为 A. 5个/米3 B. 4个/米3 C. 3个/米3 D. 2个/米3 E. 1个/米3 参考答案:E 答案解析:[解析] A级洁净工作区，动态悬浮粒子最大允许数为：“≥0.5μm者3500个/米
3
，≥5μm者1个/米
3
”。
