Question

1. order the following stars from coolest to hottest.
2. for most stars, what does a higher temperature tend to go with?

Explanation:

1. Star color indicates temperature. Red - orange stars are cooler, blue - white stars are hotter. Star B is orange, star C is blue - white, star A is white. So the order from coolest to hottest is star B, star C, star A.
2. For most stars, higher temperature is associated with higher luminosity as per the Stefan - Boltzmann law and the Hertzsprung - Russell diagram.

Answer:

1. star B, star C, star A
2. A higher luminosity