What does the phrase "cost a pretty penny" in the first paragraph mean？
A. To be very attractive.
B. To cost a lot.
C. To have big box office returns.
D. To require a lot of effort to accomplish.
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Which of the following is a kind of petal？
A. The column.
B. The sepal.
C. The stem.
D. The labellum.
Kent says that he introduced automation at his factory because he
A. wanted to make the future of the steel industry more secure.
B. thought that his men were not working hard enough.
C. needed to cut down on the running costs of the company.
D. believed it would encourage team spirit in his workforce.
How many orchid seeds are typically pollinated at one time？
A. No specific figure is given in the passgae.
B. 2,000.
C. 20,000.
D. 200,000.
Why does the author mention the Virgo galaxy and the Andromeda galaxy in the third paragraph？
A. To describe the effect that distance has no visibility.
B. To compare the ages of two relatively young galaxies.
C. To emphasize the vast distances of the galaxies from Earth.
D. To explain why certain galaxies cannot be seen by a telescope.
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