The loudness ( L ) of sound in decibels is given by ( L = 10log₁0(I/I_0) ) where ( I ) is the intensity of sound, and ( I_0 = 10⁻12 ) W/m². About how many times more intense is a 97 decibel sound than a 93 decibel sound?
a. 4 times
b. 8 times
c. 16 times
d. 32 times