Answer:
When a ray of light passes through a glass slab of a certain thickness, the ray gets displaced or shifted from the original path. This is called lateral shift/displacement.
Explanation:
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The unit measurement for sound can be expressed in terms of intensity and in decibels. The intensity of sound is the measure of its power over unit area. The common unit of measurement is in decibels. This is commonly used in measuring the extent of noise. The conversion from intensity to the decibel unit is through logarithmic function. The formula is:
dB = 10 log(I/I0), where I0 is 10^-12 Watts per square meter
Substituting the values to the equation,
84 = 10log(I/10^-12)
I = 0.0002512 W/m2
In scientific notation the intensity is 2.512 x 10^-4 W/m^2.
        
             
        
        
        
D.	Unbalanced forces are acting on it.
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