Answer:
The answer to the question is
The luminosity of stars A is four times that of star B
Explanation:
Flux (F) produced by a source of light is directly proportional to the brightness or Luminosity (L), and varies inversely to its distance d, that is [tex]F \alpha \frac{L}{d^2}[/tex]
Therefore if the two stars present the same flux then we have
[tex]\frac{L_1}{d_1^2} = \frac{L_2}{(2d_1)^2}[/tex] then crossing out like terms gives [tex]\frac{L_1}{1} = \frac{L_2}{2^2}[/tex] or 4·L₁ = L₂
The luminosity of star A is 4 times the that of star B
