Alpha Centauri A lies at a distance of 4.4 light-years and has an apparent brightness in our night sky of 2.7 * 10-8 watt/m2. Recall that 1 lightyear = 9.5 * 1012 km = 9.5 * 1015 m. a. Use the inverse square law for light to calculate the luminosity of Alpha Centauri A. b. Suppose you have a light bulb that emits 10 watts of visible light. How far away would you have to put the light bulb for it to have the same apparent brightness as Alpha Centauri A in our sky? (Hint: Use 10 watts as L in the inverse square law for light, and use the apparent brightness given