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: no it is not
Step-by-step explanation: any number that repeats forever cannot be written as a rational way or a fraction. So it is not rational.
Answer:
V = D/t = 10 / 20 = 0.5 mile per min
V = D/t = 20/30 = (2/3) mile per min
V = D/t = (10+20)/ 50 = (3/5) mile per min
Answer:
(1,0)
(-2,3)
(5,24)
Step-by-step explanation:
To solve this you can can just plug in the x and y values and see which work
y = x²-1
Lets test (0,1):
1 = 0²-1
1 = -1
This pair <em>does not</em> work, because 1 does not equal -1
Lets test (1,0):
0 = 1²-1
0 = 0
This <em>does</em> work, because 0 equals 0
Lets test (3,5):
5 = 3²-1
5 = 9 - 1
5 = 8
This pair <em>does not</em> work, because 5 does not equal 8
Lets test (5,24):
24 = 5²-1
24 = 25 -1
24 = 24
This pair <em>does</em> work, because 24 equals 24
Lets test (-2,3):
3 = (-2)²-1
3 = 4-1
3 = 3
This pair <em>does</em> work, because 3 equals 3
Lets test (-4,-17):
-17 = (-4)²-1
-17 = 16 - 1
-17 = 15
This pair <em>does not</em> work, because -17 does not equal 15
So the pairs that are on the graph are:
(1,0)
(-2,3)
(5,24)
