1. what is the most abundant gas in the atmosphere?
nitrogen
2.the form of oxygen that combines three oxygen atoms into each molecule is called? ozone
3.most important weather phenomena occur in the?
troposphere

100% correct.

a mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. this uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.a geomagnetic reversal is a change in a planet's magnetic field such that the positions of magnetic north and magnetic south are interchanged.