Logarithmic Functions

Ok, first of all, how do you put logs into your calculator?
Secondly, im not sure what to do here in this question.

The intensity of sound is messured in decibels(dB). The level of sound, L, in decibels, is given by L=10log(I/Io) ,where I is the intencity of sound and Io is the faintest sound detectable to humans.
A. Determine the level of sound that is 20 times more intence than Io, correct to the nearest decibel.
B. The level of sound in a quiet bedroom at night might be 30dB, while normal conversation has a sound level of about 60dB. How many times more intense is normal conversation than a quiet room?

A log or ln button is usually found on the calculator keypad. Generally, it depends on the calculator (graphic or not etc).

On your question,

A: For I=20*I₀ you get L=10 log(20)
B: Find the ratio of the levels of sound. If you know how to perform log calculations you should be fine.