An earthquake measured 4.2 on the Richter scale. Use the formula $\displaystyle{R}={\log{{\left(\frac{{A}}{{A}_{{0}}}\right)}}}\usepackage{cmbright}\Huge\$ to determine approximately how many times stronger the wave amplitude A of the earthquake was than $\displaystyle{A}_{{0}}\usepackage{cmbright}\Huge\$ .