Part D The Sun has a diameter of approximately 1,391,400 kilometers. How big would the Sun be in your scaled-down model of the solar system? Explain how you scaled the Sun’s diameter to fit into your model, and describe how its size compares to the planets.

About 100 times more than other planets.

Explanation:

The Sun would be about 100 times bigger than the earth planet in the scaled-down model of the solar system because in the reality the size of sun is 109 times more than the earth so making a model more perfect and nearer to reality we have to maintain the diameter of the sun more than 100 times than the earth and other planets.

it's c. (to reduce the greenhouse effect/carbon gasses)