A. has a declination equal to twice that of the Sun B. comprises two stars that appear close together C. is twice as bright as a single star D. suddenly becomes much brighter and then fade
A. 2.5 times as bright as a second magnitude star B. 3 times as bright as a second magnitude star C. 5 times as bright as a second magnitude star D. 10 times as bright as a second magnitude star
A. the Sun B. stars C. planets D. All of the above
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