4.stars on the upper left end of the main sequence differ from those on the lower right end in what way?

a. stars on the upper left end are less massive.
b. stars on the upper left end are more massive.
c. stars on the upper left end tend to be red in color.
d. stars on the upper left end are near the end of their life cycle.

all fossil fuels are nonrenewable, so think coal, gasoline, things that we will eventually run out of. all fossil fuels are nonrenewable resources, but not all nonrenewable recourses are fossil fuels. these resources are not being renewed as fast as we are using them. i hope this considering there weren't any answer choices.

what events in mexico's history might explain why the country continues to have difficulty improving social justice and economic opportunities for all people?