Предмет: Биология, автор: Аноним

Какие еще функции выполняют перья у птицы?

Ответы

Автор ответа: vdoovichenkodaria

Маховые и рулевые перья имеют важное значение для полета. Контурное перо делает форму тела обтекаемой, выполняет защитные функции, не пропускают влагу (смазаны секретом копчиковой железы). Маховые перья образуют крыло, увеличивают площадь соприкосновения с воздухом. Вот

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Прочитайте текст. Определите, какие из утверждений после текста верны (TRUE), неверны (FALSE) или не упоминаются в тексте (NOT STATED).
Measuring Snowfall
Despite the many high-tech instruments now available to scientists who study the weather, one measurement remains relatively difficult to make, and that’s calculating how much snow actually falls in any particular place during a snowstorm. This explains why the National Center for Atmospheric Research (NCAR) in the USA is experimenting with new ways of achieving a greater level of accuracy in snowfall figures. As their representative Ethan Guttmann points out, ‘You’d think it was just a matter of going out and sticking a ruler in the snow and measuring how much is on the ground. The problem is, if you move the ruler over just a few centimetres, you may get a different reading.’
In fact, the taking of measurements is complicated by a number of factors. For example, the first snowflakes may melt as soon as they hit warm surfaces, while others are whisked away by the wind, leaving some ground bare and other places buried under deep snowdrifts. Guttman’s colleagues have been testing a number of new snowmeasuring devices, including ultrasonic snow depth sensors, which send out a pulse of noise and measure how long it takes to bounce back from the surface below the snow, and laser sensors which work on the same basic principle but use light instead of sound. Another device for measuring snowfall is a type of open container with motor-vehicle antifreeze inside it. The antifreeze melts the snow as it falls and sensors measure the weight of the resulting liquid.
NCAR scientists have also experimented with using Global Positioning Satellites (GPS) to measure snow depth. It may be possible for signals sent from these satellites to measure the distance to both the surface of the snow and to the ground beneath it. Not only would this method be more cost-effective than other methods, but it might also be particularly useful for measuring the snow in remote locations such as inaccessible upland areas and the highest mountain peaks and ranges. Accurate measurement of snowfall in these areas is important as entire regions may depend on spring run-off of melted snow for their water supply.
The scientists also learned that they could improve the results of both manual and high-tech methods of snow measurement by using something known as a snow board. Basically, this is just a flat piece of white-painted wood on which snow can accumulate. Windshields placed around these can also add to the accuracy of measurements.

1) NCAR accepts the need for more precise methods of measuring snowfall.
2) Researchers have found ultrasonic sensors more reliable than laser sensors.
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4) Using GPS technology would be more expensive than using the alternative devices being tried out.
5) GPS technology could allow snowfall to be measured across a wider range of landscapes.
6) The use of a snowboard is particularly effective in areas with high winds.

Выполните задания, выбрав подходящий грамматический вариант:
1) A: "It's really hot in this room." B: "Wait. I _____ the window."
a. 'll open
b. 'm going to open
c. 'm opening
d. open
2) I _____ the tickets on Friday.
a. was buying
b. bought
c. have bought
d. buyed
3) I _____ in this village all my life.
a. live
b.' m living
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4) A: "Why are you so dirty?" B: "Because I _____ the basement."
a. clean
b. 've cleaned
c. 've been cleaning
d. cleaning
5) The new sofa isn't ____ the old one.
a. as nice as
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c. as nicer than
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Make sure you have something _____ to say before you stand up and speak (CONSTRUCT).
A new _____ centre is being built outside the town. (INDUSTRY)
She was a very _____ woman (AMBITION).

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