Identify the true statement. a. Earthquakes never have hypocenters (foci) deeper than about 100 km (60 miles). b. Seismic waves become smaller in amplitude with increasing distance from the epicenter. c. Contour lines representing Richter values are used to delimit zones of earthquake intensity; the greater the quake, the higher the intensity values and the wider the zones. d. Earthquake intensity is based on ground motion recorded by a seismograph; magnitude is based on the amount of damage produced