Is there supposed to be a picture? Next time try putting a picture
Answer: The decibel scale is a logarithmic scale where each bel or 10 decibels correspondents to a factor of ten. A power intensity of 10^(-12) watts per square meter is the standard reference for a SPL of 0 db. So an SPL of 98 db corresponds to a power intensity of 10^(9.8)*10^(-12) or 10^(9.8–12) w/m^2.
0.006309573 w/m^2.
You can also readily find the value for any given SPL using the online calculator at: http://www.sengpielaudio.com/calculator-soundlevel.htm
Explanation:
The car traverses a distance 
after time 
according to
where 
is its acceleration, 10 m/s^2. The time it takes for the car to travel 25 m is
5 is pretty close to 4, so we can approximate the square root of 5 by 2. Then the car's velocity 
after 2 s of travel is given by
which makes C the most likely answer.
Answer:
<em>a) 3.6 ft</em>
<em>b) 12.4 ft</em>
Explanation:
Distance between mirrors = 6.2 ft
difference from from the mirror you face = 1.8 ft
a) you stand 1.8 ft in front of the mirror you face.
According to plane mirror rules, the image formed is the same distance inside the mirror surface as the distance of the object (you) from the mirror surface. From this,
your distance from your first "front" image = 1.8 ft + 1.8 ft = <em>3.6 ft</em>
b) The mirror behind you is 6.2 - 1.8 = 4.4 ft behind you.
the back mirror will be reflected 3.6 + 4.4 = 8 ft into the front mirror,
the first image of your back will be 4.4 ft into the back mirror,
therefore your distance from your first "back" image = 8 + 4.4 = <em>12.4 ft</em>
Because it doesn't use energy it uses mechanical and kinetic
