展开全部

题目列表

题目内容
Centuries ago, the Maya of Central America produced elaborate, deeply cut carvings in stone. The carvings would have required a cutting tool of hard stone or metal. Deposits of iron ore exist throughout Central America, but apparently the Maya never developed the technology to use them and the metals the Maya are known to have used, copper and gold, would not have been hard enough. Therefore, the Maya must have used stone tools to make these carvings.
Which of the following, if true, most seriously weakens the argument?
This passage is adapted from an essay published in 2010.

As I write, the Large Hadron Collider, the world`s biggest atom- smasher at CERN in Geneva, has switched on with almost unprecedented media jamboree. Asked about the practical value of it all. Stephen Hawking has said that "modern society is based on advances in pure science that were not foreseen to have practical applications." It's a common claim, and it subtly reinforces the hierarchy that Medawar identified: technology and engineering are the humble offspring of pure science, the casual cast-offs of a more elevated pursuit.

I don't believe that such pronouncements are intended to denigrate applied science as an intellectual activity; they merely speak into a culture in which that has already happened. Pure science undoubtedly does lead io applied spin-offs. but this is not the norm. Rather, most of our technology has come from explicit and painstaking efforts to develop it. And this is simply a part of the scientific enterprise. A dividing line between pure and applied science makes no sense at all, running as it does in a convoluted path through disciplines, departments, even individual scientific papers and careers. Research aimed at applications fills the pages of the leading journals in physics, chemistry, and the life and Earth sciences; curiosity-driven research with no real practical value is abundant in the "applied" literature of the materials, biotechnological, and engineering sciences. The fact that "pure'" and "applied" science are useful and meaningful terms seduces us sometimes into thinking that they are real, absolute, and distinct categories.
In the context of the passage, the mention of the Large Hadron Collider primarily serves to
According to the passage, the "explicit and painstaking efforts" are
The passage implies that the statement made by Stephen Hawking has which shortcoming? A. It overstates the importance of technology for modem society.
x and y are positive integers

$$x^{2}$$+$$y^{2}$$=89

xy=40

Quantity A:|x-y|

Quantity B:3
The average (arithmetic mean) of 20 numbers is 53. When one of the numbers is discarded, the average (arithmetic mean) of the remaining numbers is 54.

Quantity A:The discarded number

Quantity B:50
d≠0

Quantity A:The area of a square region with sides of length d

Quantity B:The area of a circular region with diameter d


Quantity A:RS

Quantity B:TU
a is a positive integer.[br/\ x is the remainder when 15a is divided by 6

Quantity A:x

Quantity B:2
Thirty percent of the members of Group G are also members of Group H. Twenty percent of the members of Group H are also members of Group G.

Quantity A:The total number of members of Group G

Quantity B:The total number of members of Group H
5(x-y+20)=y+100

y≠0

Quantity A:$$\frac{x}{y}$$

Quantity B:1
n is a negative integer, and ab=1

Quantity A:$$a^{n}$$

Quantity B:$$b^{n}$$
If k, n and p are consecutive positive even integers and k < n < p, which of the following must be an integer?
In a certain club, 40 percent of the members are less than 25 years old and 66 percent of the members are less than 35 years old. Approximately what fraction of the members of the club are at least 25 years old but less than 35 years old?
On a trip, Marie drove the first half of the distance at an average speed of 30 miles per hour for a total of 13 hours of driving, and Juanita will drive the second half of the trip. They scheduled t hours driving for the entire distance. If they are to arrive exactly on schedule, at what average speed must Juanita drive the second half of the distance?
In the rectangular coordinate system, a certain line has slope 3. Which of the following pairs of points could be on the line?
As a part of an environmental study of a river, a random sample of trout was drawn from the river and the lengths of the trout were recorded. The average (arithmetic mean) length was 14.31 inches. If a length of 16.89 inches was 1.50 standard deviations above the average, what was the standard deviation of the lengths of the trout in the sample?

共收录:

25000 +道题目

137本备考书籍

最新提问