Question

a high - mass star has a
○ equally long main sequence lifetime as a low - mass star.
○ longer main sequence lifetime than a low - mass star.
○ shorter main sequence lifetime than a low - mass star.

this is because a high - mass star
○ uses up its nuclear fuel faster than a low - mass star does.
○ is larger and thus has more fuel available for nuclear fusion.
○ will not spend any time on the main sequence.
○ is more red in color than a low - mass star.

Explanation:

High - mass stars have higher core temperatures and pressures, causing them to fuse hydrogen into helium at a much faster rate than low - mass stars. Despite having more mass (fuel), the rapid consumption leads to a shorter main - sequence lifetime.

Answer:

1. C. shorter main sequence lifetime than a low - mass star.
2. A. uses up its nuclear fuel faster than a low - mass star does.