Why does the author mention a car in paragraph 2？
A. The car is an example of how conditions are used to make predictions.
B. The author digresses in order to tell a story about a car.
C. The car introduces the concept of computer models.
D. The mathematical equations for the car are very simple to understand.
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All of the following are mentioned as adaptations to the bird's anatomy to accommodate flight EXCEPT
A. a covering of feathers
B. relatively large brains
C. very sharp eyes
D. small legs and feet
According to paragraph 6, which of the following is true about the wings of birds？
All birds flap their wings constantly by using breast muscles.
B. Eagles and hawks have wings that propel them at 170 km/hr.
C. The airfoils of birds function like the wings on airplanes.
D. Wings are attached to airfoils in the bird's skeletal structure.
姐姐想买很多漂亮衣服。 ()
A. True
B. False
From this letter we can see that______.
A. people's work-load is heavy indeed these days
B. it is a letter to the government office
C. the writer thinks that the five-day work system is exciting
D. a lot of people think a day should be cut off the six-day work week
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