Help With Homework

Could someone help with some astronomy questions I have? I think my
answers are correct. I just want to make sure.

I just discovered a new planet that orbits the sun between Uranus and
Neptune.
What law would you use to determine the orbital period of the new
planet?
answer. Copernicus

Does the planet take a longer or shorter time to orbit the Sun than the
Earth does?
answer. Longer

If the new planet rotates on its axis three times slower than the earth
does, what is the length of a day (our is 24 hours) on the new planet?
answer. 8 hours

I live somewhere north of the equator. In the summer I should not be
able to see Sagittarius. In the winter I should be able to see Gemini.
In the spring I should be able to see Virgo. In autumn I should not be
able to see Pisces.

In the summer Virgo is easily visible.

Thank you