Which environmental changes are considered short term check all that apply

A short-term environmental change is drought, smog, flooding, volcanic eruption, blizzards, and pollution.

it’s lava came from an explosive eruption

to figure the total magnification of an image that you are viewing through the microscope is really quite simple. to get the total magnification take the power of the objective (4x, 10x, 40x) and multiply by the power of the eyepiece, (usually 10x)