对于单缝衍射现象,以下说法正确的是() A.缝的宽度d越小,衍射条纹越亮 B.入

题型:选择题

问题:

对于单缝衍射现象,以下说法正确的是(    )

A.缝的宽度d越小,衍射条纹越亮

B.入射光的波长越短,衍射现象越明显

C.缝的宽度d越小,光的传播路线越接近直线

D.缝的宽度d越小,衍射条纹越明显

考点:光的衍射
题型:选择题
口算.
70÷8=
50-24=26÷3=4×90=
5×6+7=3+6×8=0×4+4=56+22-13=
2
7
+
3
7
=
1-
3
10
=
5
6
+
1
6
=
1-
3
8
-
5
8
=
题型:选择题

阅读理解。

     It was Monday. Mrs. Smith's dog was hungry, but there was not any meat in the house.

     Considering that there was no better way, Mrs. Smith took a piece of paper, and wrote the following

words on it "Give my dog half a pound of meat." Then she gave the paper to her dog and said gently, "Take

this to the butcher, and he's going to give you your lunch today."

     Holding the piece of paper in its mouth, the dog ran to the butcher's. It gave the paper to the butcher. The

butcher read it carefully, recognized that it was really the lady's handwriting and soon did it as he was asked

to. The dog was very happy, and ate the meat up at once.

     At noon, the dog came to the shop again. It gave the butcher a piece of paper again. After reading it, he

gave it half a pound of meat once more.

     The next day, the dog came again exactly at noon. And as usual, it brought a piece of paper in the mouth.

This time, the butcher did not take a look at paper, and gave the dog its meat, for he had regarded the dog as

one of his customers (顾客).

     But, the dog came again at four o'clock. And the same thing happened once again. To the butcher's more

surprise, it came for the third time at six o'clock, and brought with it a third piece of paper. The butcher felt

a bit puzzled. He said to himself, "This is a small dog. Why does Mrs. Smith give it so much meat to eat

today?" 

     Looking at the piece of paper, he found that there were not any words on it!

1. The little dog went to the butcher's _____ altogether during the two days. [ ]

A. three times

B. four times

C. five times

D. six times

2. The butcher did not give any meat to the dog _____. [ ]

A. before he felt sure that the words were really written by Mrs. Smith on Monday

B. when he found that the words on the paper were not clear

C. because he had sold out all the meat in his shop

D. until he was paid enough by Mrs. Smith

3. From the story, we can know that the dog was very ______. [ ]

A. kind

B. clever

C. honest

D. foolish

4. At the end of the story, you'll find that _____.[ ]

A. the dog was clever enough to write on the paper

B. the dog dared not go to the butcher's any more

C. the butcher was told not to give any meat to the dog

D. the butcher found himself cheated (欺骗) by the dog

题型:选择题

产品质量检验机构计量认证的内容包括哪3项()。

A.测试设备的数量

B.测试设备的性能

C.测试设备的工作环境和人员的操作技能

D.准确的措施及检测数据公正可靠的管理制度

E.准确的措施及检测数据公正可靠的仪器条件

题型:选择题

风险资本家融资的初创公司比通过其他渠道融资的公司失败率要低。所以,与诸如企业家个人素质、战略规划质量或公司管理结构等因素相比,融资渠道对于初创公司的成功更为重要。
以下哪项如果为真,最能削弱上述论证

A.风险资本家在决定是否为初创公司提供资金时,把该公司的企业家个人素质、战略觇划质量和管理结构等作为主要的考虑因素。

B.作为取得成功的要素,初创公司的企业家个人素质比它的战略规划更为重要。

C.初创公司的倒闭率近年逐步下降。

D.一般来讲,初创公司的管理结构不如发展中的公司完整。

E.风险资本家对初创公司的财务背景比其他融资渠道更为敏感。

题型:选择题

对重残人员实施生活救助的政策有哪些?享受的救助标准是多少?

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