Ineed assistance with these decibels.

b, d

step-by-step explanation:

1. "the loudness of a sound in decibels (db) is given by 10 log(i / i₀), where i is the intensity of the sound (measured in watts per square meter) and i₀ is 10⁻¹² watts per square meter.   if the loudness of a normal conversation is typically 60db, what is its intensity? "

60 = 10 log(i / 10⁻¹²)

6 =   log(10¹² i)

10⁶ = 10¹² i

i = 10⁻⁶

2. "the loudness of a sound in decibels (db) is given by 10 log(i / i₀), where i is the intensity of the sound (measured in watts per square meter) and i₀ is 10⁻¹² watts per square meter.   if the intensity of a lawn mower is 10⁻³ watts per square meter, what is its loudness in decibels? "

10 log(10⁻³ / 10⁻¹²)

10 log(10⁹)

10 (9)

90