题目内容

"Salty" Rice Plant Boosts Harvests
British scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more.
Tim Flowers and Tony Yeo, from Sussex University's School of Biological Sciences, have spent several years researching how crops, such as rice, could be made to grow in water that has become salty.
The pair have recently begun a three-year programme, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice.
It is estimated that each year more than 100 hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts (妨碍生长) plants. The problem is caused by several factors. In the tropics, mangroves (红树林) that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in. In Latin America, irrigation often causes problems when water is evaporated (蒸发) by the heat, leaving salt deposits behind.
Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive.
To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plants' growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use.
Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world.
Which of the following statements about Flowers and Yeo is TRUE?

A. They are students at Sussex University.
B. They are rice breeders.
C. They are husband and wife.
D. They are colleagues at an institution of higher learning.

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Magaplane (巨型飞机)
The Boeing Corp. and Europe's Airbus consortium (财团) are preparing to offer bigger airplanes to the world's airlines. Now that talks on a joint project have broken down, Boeing is pushing a stretched (拓展的) version of 747, and Airbus is designing an all-new aircraft, known as the A3XX.
Seating 550 passengers in the basic model, and 650 in a stretched version, the 1.2 million pound A3XX will not only be the largest airplane in the world, but it will also be one of the most advanced. The outer wings and the horizontal stabilizer (as big as a smaller jet's wing) will be made of carbon-fiber composite materials, and will be the largest such structures on any aircraft except the B-2 stealth bomber (隐形轰炸机). Metal skins will be welded (焊接) together with lasers, removing thousands of fasteners.
When a strong wind strikes the A3XX's 260-foot wing, movable control surfaces will prevent it from flexing (扭曲) like a giant spring. This will make the ride smoother and will save weight by reducing the load on the wing spars (翼梁). A flexible-skinned flap (副翼) will subtly change the wing's curvature (曲面) to match the airplane's changing weight as it burns fuel on each journey.
The A3XX will carry up to 1,600 meals, filling more than 100 food and beverage (饮料) carts. To make more room for passengers, Airbus plans to put the carts in the lower hold; automatic conveyors and elevators will deliver them to the two passenger decks. Airlines have asked Airbus to look at extra features ranging from lower-deck sleeper cabins to a children's playroom.
Airbus expects to offer the A3XX to airlines in 1998, and cleliver the first aircraft in 2003.
The basic model of A3XX can carry more than 500 passengers.

A. Right
B. Wrong
C. Not mentioned

According to the passage, which of the following would worry the critics the most?

A. The unanticipated explosion of population.
B. The creation of biological solar cells.
C. The accidental spill of oil.
D. The unexpected release of destructive nficrobes.

下列说法中正确的是()。A.页眉页脚可以不同时出现B.创建图表式窗体时,如果在“轴”和“系列”区域都指下列说法中正确的是()。

A. 页眉页脚可以不同时出现
B. 创建图表式窗体时,如果在“轴”和“系列”区域都指定了字段,则必须选择Sum、Avg、Min、Max、 Count函数之一汇总数据,或去掉“轴”或“系列”区域任一字段
C. 关闭窗体的页眉/页脚后,位于这些节上的控件只是暂时不显示
D. 使用窗体向导不可以创建主/子窗体

某报社记者被派往国外常住,不应再作为报社从业人员统计。

A. 正确
B. 错误

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