脱式计算(能简算的要简算) (45+14)÷73+710519×14+1319×

题型:解答题

问题:

脱式计算(能简算的要简算)
4
5
+
1
4
)÷
7
3
+
7
10
5
19
×
1
4
+
13
19
×
1
4
7.6×35%+6.5×0.76
13
49
×21+13×
28
49
考点:分数的简便算法
题型:解答题

雅安“4•20”地震造成了部分地区的水污染.下列对水消毒的微观过程分析正确的是(  )

A.参加反应的单质是氧气

B.经消毒后的水呈碱性

C.反应中,只有一种元素的化合价发生了变化

D.该反应的基本类型是置换反应

题型:解答题

急性左心功能不全时,为减少回心血量可采取()。

A.侧卧位

B.平卧位

C.头低位

D.抬高下肢

E.坐位

题型:解答题

For a 400-year-old art form, opera had a bad fame: overweight actresses singing the words which were hard to understand in one of those romance languages you were supposed to learn in high school. And with tickets costing as much as $145 a performance, opera goers also had a certain appearance in people's mind: rich, well-dressed and old.

But now opera companies around the country are loosening their ties and kicking off their shoes in an attempt to keep opera alive and take it to a younger and not so wealthy audience.

Opera producers have found that to attract this crowd, they need to make the opera closer to common people. Because young people don't or won't come to the opera, companies are bringing the opera to them, giving performances in such unusual places as parks, libraries and public schools.

The Houston Grand Opera's choice is the public library, where it performs “mobile operas” shortened versions(剧本) of child-friendly operas. This summer's production is Hansel & Gretel. By performing smaller versions of large productions, producers are able to make people interested while keeping costs at a reasonable level. The San Francisco Opera, which will be celebrating its 75th anniversary this year, is staging Cinderella free of charge, keeping costs down by employing students from its Young Artists' Training Program.

小题1: Which is the main idea of this passage?

A. Opera is famous for its long history.

B. Opera is only performed for rich people.

C. Opera companies are trying to keep opera alive.

D. Young people are not interested in opera.小题2:The underlined phrase in the second paragraph means ______.

A. breaking up the old rules

B. changing the dresses

C. making the audience at ease

D.advertising themselves小题3:Opera companies prefer to perform short versions because ______ .

A. they can be performed in public libraries

B. short versions are easy to perform

C. it is hard to find long versions

D. they can make more people come to opera小题4:The San Francisco Opera employs students in order to ______.

A. celebrate its 75th anniversary

B. reduce the cost

C. attract young people

D. make Cinderella popular

题型:解答题

关于固定阳极X线管靶面倾角的解释,正确的是

A.靶面与X线管短轴的垂直面的夹角
B.靶面与X线管长轴的垂直面的夹角
C.靶面与水平面的夹角
D.靶面与竖直面的夹角
E.靶面与X线管长轴的平行面的夹角

题型:解答题

在采用PID调节器的定值控制系统中,当Ti、Td均减小时,系统可能出现()

A.非周期过程

B.振荡趋势增强

C.较大静差

D.稳定性增强

更多题库