The mineral hausmannite, Mn3O4, which contains both manganese(II) and manganese(III) ions, is formed from heating manganese(IV) oxide to 890°C.
3 MnO2(l) → Mn3O4(s) + O2(g) (at 890°C)

answer; natural resources;

i don't see a text, but i am gonna assume this *orbit* the curved path, usually elliptical, described by a planet, satellite, spaceship, etc., around a celestial body, as the sun.

the answer is:  

line graphs show patterns in data with variables that change over time; whereas, circle graphs show data as parts out of a whole (such as out of 100%).