Question:
What is the inclination of Pluto's orbit? Is it almost perpendicular to the other orbits? Is this why it is no longer considered a Planet?
Answer:
As of now, Pluto has a similar orbital inclination as that of Earth, and has had it for at least a few million years. Thus, that's not why it was no longer considered a planet. In fact, it's still a planet, it's just referred to as a "dwarf" one. What lead to the change was the fact that it's not big enough to dominate the numerous objects in nearby orbits of the Kuiper Belt. The same applies to the other four that, for now, are also classified as dwarf planets: Ceres (main belt, between Mars and Jupiter), Eris, Haumea and Makemake. As for the orbital inclination, it's not so extreme! In fact, it's about 17º with relation to Earth's.