[填空题]
The sound intensity level, D, in decibels (dB), can be mwh/0gyk il73 modelled by the functiq9o/vot 0c*h8 kot:l bon
9kqv o:b* 8o/hlc tt0o D(I)=10$log_{10}$(I)+120,I≥0,
where I is the sound intensity, in watts per square meter (W /$m^2$).
1.A vacuum cleaner has a sound intensity of 1.6$\times10^{−5}$ W /$m^2$. Calculate the intensity level of the vacuum cleaner. D = dB
2.A fire truck siren has an intensity level of 124 dB. Find the sound intensity of the siren. I ≈ W /$m^2$