Answer:

Explanation:
The sound intensity level β can be mathematically defined as

where
is the reference intensity and is equal to
.
Now,

Answer:
the phase difference is 1.26 radian
Solution:
As per the question:
Distance, d = 2 m
Distance from the other speaker, d' = 2.1 m
Frequency, f = 680 Hz
Speed of sound, v = 340 m/s
Now,
To calculate the phase difference,
:
Path difference, 
For the wavelength:

where
c = speed of light in vacuum
= wavelength
Now,


Now,
Phase difference, 

Answer:
the answer is A because
from tate 4 dozen is 48 and from joe the sixth multiple of eight is 48
Answer: Approximately 3.65 hours
Explanation:
55 km/h x 3.65 hrs = 200.75 Km/h
The statement that accurately describes a proper use of eyeglasses is statement A. Using converging lenses to help a nearsighted person by moving the image from in front of the retina to the retina.