What creates the two poles in a magnet? Quick!

Which is not a source of noise pollution? a)airplanes b)acid rain c)machines d)cars

Two identical 82 mg dust particles very far apart (pee 0) are moving directly toward each other at a speed of 3698 m/s. the charge on each is-719 ? c. determine how close they will get to each other. let k = 9x109 n-m2/c2 & ignore gravity.

The image below shows numerous volcanic mountains in the pacific northwest. what is the most likely cause of the volcanic and earthquake activity in this region?