What is the purpose of the global positioning system?

a.

to find exact location using satellite signals and receivers

b.

to take aerial photographs using planes and weather balloons

c.

to study weather patterns using radio waves

d.

to analyze maps with software by combining them with data

Almost 98% of earthquakes occur at the boundary of a tectonic plates when they slide against one another. despite this, indiana still has seismic zones that experience increased seismic activity. this is particularly heavy in the wabash valley fault zone in the southwest corner of the state. how do you explain how seismic activity is felt in this area?