Sound pressure level L in decibels is given by $L=20log\frac{p}{{p}_{0}}$, where p is the sound pressure and ${p}_{0}$ is a reference pressure. The sound pressure level of a jet engine is 145 decibels, when ${p}_{0}$ is the sound pressure at the threshold of hearing, $2\times {10}^{-5}$ pascal. a. Write and solve an equation to find the sound pressure p of the jet engine to the nearest pascal. b. How many times the sound pressure at the threshold of hearing is the sound pressure of the jet engine?