Option B:

Solution:
Given sound level = 120 decibel
To find the intensity of a fire alarm:

where 
Step 1: First divide the decibel level by 10.
120 ÷ 10 = 12
Step 2: Use that value in the exponent of the ratio with base 10.

Step 3: Use that power of twelve to find the intensity in Watts per square meter.


Now, do the cross multiplication,




Option B is the correct answer.
Hence
.
brian has 2 friends over his house. he has 12 cookies and wants to split them evenly amongst them 3. how many cookies does each friend get?
Answer:
The formula to find the radius is diameter/pie. Also, it does not show the formula that they are asking.
Step-by-step explanation:
Answer:
The worth of car at the start of 2014 = $12000
The value of the car decreased 30% every year.
At start of 2015:
30% of 12000 = \frac{30}{100} \times 12000
100
30
×12000 = 3600
So, the value of the car at start of 2015 = 12000-3600 = $8400.
At start of 2016:
30% of 8400 = \frac{30}{100} \times
8400
100
30
×8400 = 2520
So, the value of the car at start of 2016 = 8400-2520 = $5880.
At start of 2017:
30% of 5880 = \frac{30}{100} \times
5880
100
30
×5880 = 1764
the value of the car at start of 2017 = 5880-1764 = $4116.
So, the value of his car at the start of 2017 is $4116.
F-1(x)=x/4 represents the inverse function because to find the inverse you have to interchange the variables & solve for y