21.The text is about...A. how earth spins around the sun
B. how night and days appear
C. what earth is
D. the distance between earth and sun

22.Where does the imaginary line go from?
A. sun to the earth
B. all around the earth
C. from one country to another country
D. from the north pole to the south pole

23.How long does it take for the earth to revolve around the sun?
A. An hour
B. 24 hours
C. A year
D. 48 hours

24.The correct statement based on the text is...
A. the sun moves around the earth
B. sun spins on its axis
C. the sun sets at day time
D. the earth turns on its axis every 24 hours

25.If night comes, it means the earth is
A. facing the sun
B. stops turning on its axis
C. facing away from the sun
D. spins faster around
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