Sound level related to intensity?

Question

What sound level change corresponds to a factor of two change in intensity?
A. 0.5 dB
B. 2 dB
C. 3 dB
D. 5 dB

Answer 1

β=10 log I / Iο
β2=10 log I2 / Iо
β2-β=10 log I2 / Iо - 10 log I / Iо
=10 log I2 / Iо / I / Iо
= 10 log I2 / I
= 10 log 2 I / I
= 10 log 2 = 10 x o.3 = 3

I hope i helped you, sorry if i have done any mistake.

Answer 2

C