Help me with chemistry! I got this answer wrong , what would be the right one?

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

What reaction is taking place? 02 + c3h8 = h20 + co2

What is the molar mass of a gas that has density of 2.054 g/l