水滴石穿:水珠不断滴在一块石头上,经过40年,石头上形成一个深为4.8cm的小洞

题型:选择题

问题:

水滴石穿:水珠不断滴在一块石头上,经过40年,石头上形成一个深为4.8cm的小洞,则平均每个月小洞增加的深度(单位:m,用科学记数法表示)为(  )

A.4.8×10-2m

B.1.2×10-4m

C.1×10-2m

D.1×10-4m

考点:科学记数法和有效数字
题型:选择题

“人贵有自知之明”这说明我们要全面了解自己,可以

A.在多重比较中认识自己

B.在自我观察和内省中认识自己

C.通过镜子认识自己

D.从别人的态度中认识自己

题型:选择题
阅读理解。

       1   If not, and if right now you're not focusing on this article, your time might be better spent on a short
nap (小睡) to boost (促进) your focus and productivity (效率).
     That's what the National Sleep Foundation says, and it's a message that health education professionals at
the University of California at Davis (a city of California, America) have been spreading to their students.
     "We're familiar with the benefits of sleep," said Amelia, a student in sleep and stress at the UC Davis health
center.   2   For students, the benefits of increased productivity and focus will help their scores-even though
there is no data to back that up.
     However, research has repeatedly shown that when students have 7-9 hours of sleep, 20-30 minute naps
do offer these benefits,   3   
     So Jason B. Spitzer, a health educator, believes encouraging students to take naps to improve their state of
mind-not to mention stay awake during classes - is very important.
     Health educators discovered that while 33 percent of Davis students didn't nap at all, three-quarters of those who did nap did so for too long-more than 30 minutes. That told the educators that a napping campaign would
have to focus on two different populations:   4   Health educators hand out "nap tools"; they include earplugs
(耳塞), an eye mask and a tip card with directions to more messages online. They advertise in the student
newspaper introducing napping tips and benefits, and they team with the student government to spread the
word on napping during National Sleep Awareness Week. 
       5   "We want to improve their napping and their sleep quality." Spitzer said.

A. Did you get a complete and restful night's sleep last night?
B. non-nappers and long nappers.
C. The Davis campaign is still changing every year.
D."We're not familiar with the positive effects of napping."
E. We should try our best to nap when it is necessary.
F. Napping is very important to us.
G. particularly when taken between the hours of 10 to 11 am or 2 to 4 pm.
题型:选择题

以下程序的输出结果是( )。 #include<iostream.h> main() { int m=5; if(m++>5) cout<<m; else cout<<m--; }

A.7

B.6

C.5

D.4

题型:选择题

下列关于百日咳鲍特菌叙述不正确的是()

A.革兰阴性小杆菌

B.专性需氧

C.无芽孢、有荚膜

D.K抗原中7因子是百日咳鲍特菌、副百日咳鲍特菌和支气管炎鲍特菌所共有

E.抵抗力强,对紫外线不敏感

题型:选择题

写出Rijndael轮函数(普通轮)的四个不同的计算部件名称。

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