Answer
Whisper: $D\approx 21$ DB
TV: $D\approx 75$ DB
Loud music: $D\approx 120$ DB
Jet aircraft: $D\approx 140$ DB
Work Step by Step
$D=10\displaystyle \log\frac{I}{I_{0}}$
Whisper: $D=10\displaystyle \log\frac{115\times 10^{-12}}{10^{-12}}\approx 21$ DB
TV: $D=10\displaystyle \log\frac{320\times 10^{-7}}{10^{-12}}\approx 75$ DB
Loud music: $D=10\displaystyle \log\frac{900\times 10^{-3}}{10^{-12}}\approx 120$ DB
Jet aircraft: $D=10\displaystyle \log\frac{100}{10^{-12}}\approx 140$ DB
