If it takes a planet 8 years to orbit the Sun how long (in years) will it take the planet to go all the way around our sky once?

The planets have orbits of varying periods: the further out they are, the longer it takes them to orbit the sun. Earth takes one year to orbit the sun, Mercury, the planet closest to the sun, takes about 3 months, and Neptune, the planet furthest from the sun, takes nearly 165 years.