Solve
-Use the Formula $R = \log \left( \frac { \mathrm { a } } { \mathrm { T } } \right) + \mathrm { B }$

Multiple Choice

Solve.
-Use the formula $R = \log \left( \frac { \mathrm { a } } { \mathrm { T } } \right) + \mathrm { B }$ to find the intensity $\mathrm { R }$ on the Richter scale, given that amplitude a is 438 micrometers, time T between waves is $3.1$ seconds, and B is 3.1. Round answer to one decimal place.

A) $8.5$
B) $2.2$
C) $5.3$
D) $8.1$