下列实验中所选用的仪器合理的是 A.用100mL量筒量取5.2mL的稀硫酸 B.

题型:选择题

问题:

下列实验中所选用的仪器合理的是

A.用100mL量筒量取5.2mL的稀硫酸

B.用500mL容量瓶配制500mL0.2mol /L的NaOH溶液

C.用托盘天平称量11.75gNaCl晶体

D.用分液漏斗进行固体和液体的分离

考点:化学实验的基本操作化学实验安全危险化学品的标志化学药品的变质
题型:选择题

阅读理解。

     Mr. and Mrs. Jones were going on their vacation  with their children, and they must arrive at the

airport before 11:40 the next morning. "It takes us thirty minutes to get there in a car," Mr. Jones said,

"so we must get ready before eleven o'clock. Don't be late."

     At ten-fifty, all of them were busy doing something, but Mrs. Jones wasn't. She sat quietly in a chair

in the garden and enjoyed the good weather.

     Mr. Jones and the children were surprised, but Mrs. Jones said, "Don't worry! Before I went to bed

last night, I made all our clocks and watches twenty minutes ahead (提前). Now we can get to the

airport early."

1. Why did the Jones family have to be ready before eleven o'clock?

A. Because they were going to a party.

B. Because they must arrive at the airport at 11:40.

C. Because they had to go to a town.

2. How long does it take to go from Mr. Jones' house to the airport by car?

A. Twenty minutes.

B. Thirty minutes.

C. Fifty minutes.

3. Mr. Jones and the children were _____ when they saw Mrs. Jones sitting in the garden.

A. sad

B. happy

C. surprised

4. Why did Mrs. Jones sit quietly?

A. Because she made all the clocks and watches ahead and they wouldn't be late.

B. Because she didn't like to spend her vacation.

C. Because she wanted to stay at home.

5. What time was it in fact when Mr. Jones and the children were busy doing things?

A. It was ten-fifty.

B. It was eleven-ten.

C. It was ten-thirty.

题型:选择题

综合布线系统中水平子系统线缆的长度限制为()。

A.180m

B.120m

C.90m

D.60m

题型:选择题

以下程序的输出结果是______。
#include<stdio.h>
#define FUDGE(y) 2.84+y
#define PR(a)printf("%d\n",(int)(a))
#define PRINT1(a) PR(a);putchar('\n')
main()
int x=2;
PRINT1(FUDGE(5)*x);

A) 11
B) 12
C) 13
D) 15

题型:选择题

小华认为法律或道德是一种社会契约,根据柯尔伯格的道德发展理论,小华的道德判断属于()。

A.服从与惩罚定向

B.使他人愉快和帮助他人定向

C.尽义务、重权威和维持现有社会秩序

D.墨守法规和契约的定向

题型:选择题

以下选项()满足晶阐管触发电路的基本要求。

A.强触发脉冲

B.触发脉冲与电源不同步

C.与主电路电源隔离

D.抗干扰能力强

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