The bat is a marvel of evolutionary
adaptation. Most of them roost during the day, and are active at night or
twilight for they can avoid objects in the dark. I have seen this phenomenon at
work. In my youth I used to explore old mining shafts in the Randsburg district.
Sometimes my intrusion disturbed clans of bats that were hanging upside down in
the dark caves. They would fly about to evident panic, but the panic was mine, not theirs. Some flew crazily out into the daylight but some merely returned to their perches. None ever touched me, much to my relief. They may exist but I have never seen a stuffed nylon bat. To children, bats may not be as lovable as koala bears. Perhaps manufacturers do not regard them as marketable. It is not so much their hideous faces and winged bodies that have caused us to get rid of bats, but A. bats destroy crop-damaging insects B. bats are the marvel of evolution adaptation C. bats suck the blood of dying people D. bats inspire disgust based on some traditional beliefs [简答题]三角高程测量的步骤。
[判断题]钳形相位伏安表长期不用时,最好在钳头张合处涂上硅脂,以免生锈。
A.正确 B.错误 [单选题] 患者,男性,70岁。需输1000ml液体,用滴系数为15的输液器,每分钟40滴,输完需用
A.2小时15分钟 B.2小时45分钟 C.4小时15分钟 D.4小时45分钟 E.6小时15分钟 [填空题]在进行接触网作业时,作业组有关人员应携带 ( )并确保联系畅通。( 普速安规第十二条)
[单项选择]下列苷键水解方法中能获知苷键构型并保持苷元结构不变的是
A. 酸催化水解 B. 碱催化水解 C. 酶催化水解 D. Smith降解 E. 乙酰解 [单选题]在昼间遇降雾,暴风雨雪及其他情况,致使调车信号及调车手信号显示距离不足()时,应使用夜间信号。
A.1000m B.500m C.400m D.200m [多选题]下列属于呼吸保护类器材的是( )。
A.空气呼吸器 B.氧气呼吸器 C.防毒面具 D.移动供气源 [简答题]分子筛的吸附特性有哪些?
[多选题]二级动火区,是指一级动火区以外的所有()
A.防火重点部位 B.防火重点场所或设备 C.禁火区域 D.油料储存区域 [判断题]断路器液压机构油泵打压超时,检查油泵电源是否正常,如空开跳闸可试送2次,再次跳闸应查明原因。
A.正确 B.错误 [单选题]在工作和生活中如果不了解基本的科学常识,往往会引发严重的后果。遇到下列情况,正确的做法是( )。
A.厨房煤气泄露,迅速开启排风扇 B.进入久未开启的菜窖前,先要做灯火试验 C.煤矿井下停电,赶快引燃火把照明,迅速离开现场 D.室内起火,立即敞开门窗 我来回答: 提交
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