Seismic activity tells us what?
when a volcano will erupt plasma and formed elements Extremes of temperature speed at which sound moves created hole over Antarctica how strong a hurricane will be How fast a vehicle is going the strength and magnitude of an earthquake
A B C D E F G H
The seismometer will check for seismic activity.
Seismic activity tells us the strength or magnitude of an earthquake. 
Seismic activity tells us what? (A) when a volcano will erupt (B) plasma and formed elements (C) Extremes of temperature (D) speed at which sound moves (E) created hole over Antarctica (F) how strong a hurricane will be (G) How fast a vehicle is going (H) the strength and magnitude of an earthquake