It would be almost impossible to calculate the diameter of all the planets in inches, so your question can't really be answered. Plus, there are so many planets out there, so even calculating that in miles or kilometers would be pretty much impossible.
The circumference of the planets in inches is the circumference of the planets in kilometers multiplied by 39,370.0787. Do the math yourself.
All planets have gravity to some degree due to their mass. Gravity is what keeps objects, including planets, in orbit around the sun.
Neptune has only 1 sun, like all planets
All of them.
Probably, but impossible to tell as we are only just seeing planets within our own galaxy.
All planets have a core.
There are 13 in total (as of February 2013) including ALL the 5 dwarf planets!
i think we only have it and and all the rest have a phase
All of the inner planets; Mercury, Venus, Earth and Mars have less than 3 moons, while all four outer gas giant planets have many moons.
The number of planets is not known. The number of stars is not known either, nor if all have planetary systems. Certainly many billions of billions.
All except Mercury.
there are 139 moons altogether.