they are called "cells"
hope this is the answer is what your looking for.
Answer
given,
I is the loudness of sound
I = 10 Log₁₀ r
r is relative intensity
at when relative intensity is 10⁶
I = 60 dB
how much louder when 100 people would be talking together
I = 10 Log₁₀ r
I = 10 Log₁₀ (10⁶ x 100)
I = 10 Log₁₀ (10⁸)
I = 80 dB
hence, the intensity will be increased by (80 dB -60 dB) 20 dB when 100 people start talking together.
Move the decimal point to:
Left : (if the exponent of ten is a negative number -) ... OUR CASE HERE (-2)
or to
Right : (if the exponent is positive +).
You should move the point as many times as the exponent indicates.
Do not write the power of ten anymore.
So, standard form is:
Two points to the left {Exponent of Ten is Negative (-2)}
0.059 ... (without the 10)
I think that would be c) mirror because mirrors reflects light and can't create it.
