12.From what I've read, white stars are hotter than red ones. But a white dwarf would have just heavy elements to fuse, so shouldn't it be less bright?
13. Neither of those answers is correct, it's actually 4.8 (even check with google)
14. (B) Vega
15. M2lab is its Spectral type
(here are some extra facts :)
Magnitude: 0.42 Radius: 820.9 million km (1,180 R☉) Surface temperature: 3,500 K Absolute magnitude: -5.85 Mass: 1.531 × 10^31 kg (7.7 M☉) Did you know: Betelgeuse is the fifth-nearest supernova candidate by distance (640 light years)