Question #6418709Single Choice
Algebra-2
Question
The brightness B of a star as observed from Earth varies inversely with the square of its distance d from Earth. If a star is observed to have a brightness of 100 units when it is 5 light-years away, what would the brightness of the star be if it were observed from a distance of
Options
A
10 units
B
4 units
C
5 units
D
2.5 units
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