Answer:
66.6 kg
Explanation:
The weight of a person at Earth's surface is given by

where
m is the mass of the person
is the acceleration of gravity
The person in the problem has a weight of
W = 653 N
Therefore, we can rearrange the equation to find his mass:

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.
the answer is the speed of blue ball after collision is 2.6v