问题 选择题

把0.000083用科学记数法表示为

A.8.3×10-4

B.83×10-4

C.8.3×10-5

D.83×10-5

答案

答案:C

分析:科学记数法的表示形式为a×10n的形式,其中1≤|a|<10,n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值大于10时,n是正数;当原数的绝对值小于1时,n是负数.

解答:解:0.000 083用科学记数法表示为8.3×10-5

故选C.

多项选择题
单项选择题

The amazing success of humans as a (91) is the result of the evolutionary development of our brains which has led, among other things, to tool-using, tool-making, the (92) to solve problems by logical reasoning, thoughtful cooperation, and language. One of the most striking ways in which chimpanzees biologically (93) humans (94) in structure of their brains. The chimpanzee, with the capacity for (95) reasoning, (96) a type of intelligence more like that of humans than (97) any other mammal living today. The brain of the modern chimpanzee is probably not too dissimilar (98) the brain that so many millions of years ago (99) the behavior of the first ape man.
For a long time, the fact that prehistoric people made (100) was considered to be one of the major (101) distinguishing them from other creatures. (102) pointed out earlier, I have watched chimpanzees (103) grass stems in order to use them to probe for termites. It is tree that the chimpanzee does not (104) tools to "a regular and set pattern"—but then, (105) people, before their development of stone tools, undoubtedly poked around (106) sticks, and straws, at which stage it seems (107) , that they made tools to a set pattern either.
It is because of the close (108) in most people’s minds of tools with humans (109) special attention has always been focused upon any animal able to use an object as a tool: but it is important to realize that this ability, on its own, does not necessarily indicate any special intelligence in the creature (110) .

A.resemble

B.correspond

C.approach

D.follow