Background: The longest part of a star's life is called the main sequence. The time a star lasts on this depends on the amount of fuel it has (based on the hydrogen fusion in its core) and rate at which it's radiating that energy away (the luminosity). Note that the first part of this calculation is the same as what you did earlier in the semester when you determined the mass energy available to a star. a. Predict and Explain: Predict which main sequence star in Your Personal Constellation should have the longest main sequence lifetime and which should be shortest. Explain whether these lifetimes should be much more, much less, or roughly the same as the lifetime of the Sun. Explain your answer. b. Calculate: Use the mass and luminosity of at least 3 main sequence stars in Your Personal Constellation to calculate the main sequence lifetimes of these stars, including both of the ones you selected in part a. Only select main sequence stars. Give your answer in seconds and in years. c. Compare: Explain whether or not the answer to b seems to be a reasonable number. Does it agree with your prediction in a? If not, explain where the error is likely, in the calculation or in the prediction? How can you tell