# math

posted by
**Anonymous** on
.

A seismograph 300 km from the epicenter of an earthquake recorded a maximum amplitude of 4.9 * 10^2 µm. Find this earthquake's magnitude.

posted by
**Anonymous** on
.

A seismograph 300 km from the epicenter of an earthquake recorded a maximum amplitude of 4.9 * 10^2 µm. Find this earthquake's magnitude.