the eruption of Mt. St. Helens was Group of answer choices Related to the subduction of the Juan de Fuca oceanic plate A total surprise Within hours of the first earthquake A gentle eruption

2,407.2 miles. or 32 hours.

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.