9、(本小题满分12分证明:(1)∵B、C分别是棱PB、P℃的中点BC1∥BCBC平面BCDE,BCC平面BCDEBC1∥平面BCDE3分BCC平面BCDE,平面BCDE∩平面BCDE=DEBC∥DE5分DE/ BC6分(2)法VABC-ABS VRABC-VR-ABSYG PABX6X8、3√345243BC--7E法二:取PA中点F,连接F,C1FAc-ABcPAic+YA-FBf 34(.×6×8-×32×4+×3×2)3法三:取PA中点F,连接F,C1F法三:取PA中点F,连接F,C1FARC网G+32×24阿32+×3×6×6)×42l312分

C28.A。细节理解题。根据第二段中的“ You might think the high heat from fire would kill these organisms,but one study mentioned in the article found that some bacteria even multiply after fires."可以看出,这些微生物不会被高温杀死,有些细菌反而在大火后还会增加。故选A29.B。细节理解題。根据第三段中的“ Many bacteria and fungi don' t cause lung infections, says Chen,butit's certainly possible that a significant number could worsen symptoms in someone with a preexisting lungcondition."可以知道,许多细菌和真菌不会引起肺部感染,而是会使已经存在的肺病症状恶化。故选B30.D。细节理解題。根据第四段中的“ This is especially true for lower- income populations, Jack says,because people with fewer protective means are often more exposed to the environment.”可以看出,烟雾会传播疾病这件事对低收人的人群有更大的影响,是因为他们更多地直接接触环境。故选D。31.C,推理判断题。Dr.Chen在最后一段给了一些关于如何避开恶劣空气的具体建议。,故选C

以上就是2021-2022英语周报八年级新目标29期答案，更多英语周报答案请关注本网站。

本文地址： http://www.ncneedu.cn/post/18900.html

文章来源：admin

版权声明：除非特别标注，否则均为本站原创文章，转载时请以链接形式注明文章出处。