在MapReduce编程模式中，Map任务与Reduce任务的数量分别是（）？

A:一个Map任务，多个Reduce任务 B:多个Map任务，多个Reduce任务 C:一个Map任务，一个Reduce任务 D:多个Map任务，一个Reduce任务

下面关于MapReduce模型中Map函数与Reduce函数的描述正确的是（）

A:一个Map函数就是对一部分原始数据进行指定的操作 B:一个Map操作就是对每个Reduce所产生的一部分中间结果进行合并操作 C:Map与Map之间不是相互独立的 D:Reduce与Reduce之间不是相互独立的

Passage One 1
There is an English saying," Laughter is the best medicine." Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it bas on the human body. They have found that laughter really can improve people’s health.
Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart beating and breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.
Other tests have shown that laughter appears to be able to reduce the effect of pain on the body.. In one experiment doctors produced pain in groups of students who listened-to different radio programs. The group that tolerated the pain for the longest time was the group which listened to a funny program. The reason why laughter can reduce pain seems to be that it helps to produce a kind of chemicals in the brain which diminish both stress and pain.
As a result of these discoveries, some doctors in the United States now hold laughter clinics, in which they help to improve their patients’ condition by encouraging them to laugh. They have found that even if their patients do not really feel like laughing, making them smile is enough to produce beneficial effects similar to those caused by laughter.

A:test B:stop C:reduce D:increase

Passage One
There is an English saying," Laughter is the best medicine." Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it bas on the human body. They have found that laughter really can improve people’s health.
Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart beating and breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.
Other tests have shown that laughter appears to be able to reduce the effect of pain on the body.. In one experiment doctors produced pain in groups of students who listened-to different radio programs. The group that tolerated the pain for the longest time was the group which listened to a funny program. The reason why laughter can reduce pain seems to be that it helps to produce a kind of chemicals in the brain which diminish both stress and pain.
As a result of these discoveries, some doctors in the United States now hold laughter clinics, in which they help to improve their patients’ condition by encouraging them to laugh. They have found that even if their patients do not really feel like laughing, making them smile is enough to produce beneficial effects similar to those caused by laughter.

A:test B:stop C:reduce D:increase

Climate Change Poses Major Risks for Unprepared Cities A new examination of urban policies has been carried out recently by Patricia Romero Lankao. She is a sociologist specializing in climate change and________(51) development. She warns that many of the world’s fast-growing urban areas, especially in developing countries, will likely suffer from the________(52) of changing climate. Her work also concludes that most cities are failing to________(53) emissions of carbon dioxide and other greenhouse gases. These gases are known to affect the atmosphere. “Climate change is a deeply local issue and poses profound ________ (54) to the growing cities of the world.” says Romero Lankao. “But too few cities are developing effective strategies to protect their residents. ” Cities are ________ (55) sources of greenhouse gases. And urban populations are likely to be among those most severely affected by future climate change. Lankao’s findings highlight ways in which city-residents are particularly vulnerable, and suggest policy interventions (干预) that could offer immediate and longer-term _________ (56). The locations and dense construction patterns of cities often place their populations at greater __________ (57) for natural disasters. Potential threats associated with climate include storm surges and prolonged hot weather. Storm surges can flood coastal areas and prolonged hot weather can heat ________ (58) paved cities more than surrounding areas. The impacts of such natural events can be more ________ (59) in an urban environment. For example, a prolonged heat wave can increase existing levels of air pollution, causing widespread health problems. Poorer neighborhoods that may ________ (60) basic facilities such as drinking water or a dependable network of roads, are especially vulnerable to natural disasters. Many residents in poorer countries live in sub-standard housing ________ (61) access to reliable drinking water, roads and basic services. Local governments, therefore, should take measures to ________ (62) their residents. Unfortunately, they tend to move towards rhetoric (言辞) ________ (63) meaningful responses, Romero Lankao writes. They don’t impose construction standards that could reduce heating and air conditioning ________ (64). They don’t emphasize mass transit and reduce automobile use. In fact, many local governments are taking a hands-off approach. ________ (65), she urges them to change their idle policies and to take strong steps to prevent the harmful effects of climate change on cities.

A:reduce B:increase C:study D:measure

In recent years, there has been an increased awareness of the importance of protecting the environment. The three Rs to keep in mind for a cleaner environment are: reduce, reuse, and recycle.
First, reduce how much you use. It means shopping with the environment in mind. Consider the environmental impact of each product before you buy it. Make a list of what you need before you go shopping; this will reduce impulse buying. Buy in bulk - its cheaper and eliminates small containers and excess packaging. Besides, bulk merchandise may be shared with friends or neighbors. You should also avoid buying things that can’t by recycled.
A shopping list can help

A:find cheaper items. B:reduce impulsive buying. C:eliminate small containers. D:avoid excess packagin

The government may reduce taxes in a recession in order to _________.

A:apply to all businesses. B:raise the GDP. C:state and city government D:reduce spending E:modify fluctuations in the business cycle F:produce and sell goods

To round is to delete or (66) one or more of the least significant digits in a positional (67) and to, or not to, adjust the part retained in accordance with some specified rule. The purpose of rounding is usually to limit the (68) of the numeral or to reduce the number of characters in the numeral, or to do both these things.
The most common arithmetic forms of rounding are rounding down, rounding up and rounding off. Rounding down is defined as making no adjustment to the part of the numeral that is retained. Rounding up means adjusting the part of the numeral that is retained by adding 1 to the least significant of its digits and executing any necessary carries, if and only if One or more non-zero digits have been deleted. Rounding off (69) adjusting the part of the numeral retained by adding 1 to the least significant of its digits and executing any necessary carries, if and only if the most significant of the digits deleted was equal to or greater than half the (70) of its digit place.

A:simplify B:reduce C:abbreviate D:omit