By 272.7 degrees angle has planet Y rotated through during this time.
The cubes of the semi-major axes of the planets' orbits are precisely proportional to the squares of the planets' orbital periods. According to Kepler's Third Law, as an orbiting planet's radius rises, so does the time of its orbit around the Sun.
Using Kepler's 3rd law, which says that the period of any planet's orbit squared is proportional to the radius of the orbit cubes, we can establish that
(period X / period Y)^2 = (radius X / radius Y)^3
(period X / period Y)^2 = 2^3 = 8
take sq root
period X / period Y = √8 = 2.82≅ 3
this means it takes planet X 2.82≅ 3 times longer to go through one orbit... so planet Y travels 2.82≅ 3 times as far (in its orbit...) as planet X!
This means...
planet Y travels 3 * 90.9 = 272.7 degrees
to learn more about Kepler's 3rd law go to - https://brainly.com/question/16705471
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