Given: Sound Intensity ( I ) = 
We know, the approximate threshold of human hearing is at 1kHz. In watts/m^2 it's value is
⁻¹² W/m².
So, we can say, Reference sound intensity
= 10⁻¹² W/m².
We have formula for "sound intensity level LI in dB" when entering sound intensity.
LI = 10×log (I / Io) in dB
Plugging values of I and Io in formula.
LI = 10 × log (
)
LI = 10 × log (99000000)
= 10 × 7.99564
LI = 79.96 dB.
Therefore, 79.96 dB is the sound level for a noise that has an intensity of 9.9 × 10-5 watts/m2.
Answer:
<h2>The height is 87.5 in</h2>
Step-by-step explanation:
We can solve the height of a square pyramid using the Pythagoras theorem, this is because the slant height the height and the section of the base form a right triangle
the slant height is equivalent to the hypotenuse
the height is equivalent to the opposite
while the base(half) is the adjacent
Given
the base of the pyramid= 
the adjacent is = 
the slant height (hypotenuse)= 
we know that Pythagoras theorem states that "The sum of the squares of the lengths of the legs of a right triangle ('a' and 'b' in the triangle) is equal to the square of the length of the hypotenuse ('c').


substituting we have

Answer:
The answer for this problem is x^2+x-12
Answer:
5 1/2.
Step-by-step explanation:
11 divided by 2 is 5 with a remainder of 1.
So the mixed number is 5 1/2.
Answer:
Step-by-step explanation:
(1). A = π r²
A = 4 π
Area of shaded region is
=
or
(2). C = 4 π
In this case, the length of the bigger arc and the area of shaded region happen to be the same.
The length of the arc ADB is
or