Answer:
1) move away from the windows.
When abrupt changes in pressure (produced by the hurricane) affect the windows, they can "explode" and be a serious danger for the people.
2) Go to the lowest level of the building.
Is safer than the upper levels because the lower levels suffer less from the strength of the hurricane (being closer to the ground increases the structural resistance), make sure that you have everything you may need in case of an emergency.
Answer:
The value is 
Explanation:
From the question we are told that
The emitted frequency increased by 
Let assume that the initial value of the emitted frequency is

Hence new frequency will be 
Generally from Doppler shift equation we have that
![f_1 = [\frac{ v \pm v_o}{v \pm + v_s } ] f](https://tex.z-dn.net/?f=f_1%20%3D%20%20%5B%5Cfrac%7B%20v%20%5Cpm%20v_o%7D%7Bv%20%5Cpm%20%2B%20v_s%20%7D%20%5D%20f)
Here v is the speed of sound with value 
is the velocity of the sound source which is
because it started from rest
is the observer velocity So
Generally given that the observer id moving towards the source, the Doppler frequency becomes
=>
=> 
Answer:
<em> The intensity would be 0.01432 W/</em>
<em></em>
Explanation:
The sound intensity is the power that is transmitted by a sound wave per unit area.
Given that
Power output P of the 75-piece orchestra = 72.0 W
The listener's distance r = 20.0 m
The intensity of sound waves (I) can be obtained with the expression below;
I = P/A .............. 1
where P is the power
A is the area, in this case, at the distance r the sound is radiated through a sphere.
A = area of a sphere = 4π
putting it into equation 1, the intensity would be;
I = P/ 4π
Substituting our values we have;
I = 72.0 W / 4 π

I = 0.01432 W/
Therefore the intensity would be 0.01432 W/
Hi there,
Burning fossil fuel should be a cause. Using aerosols also would be a cause.
Smog is an effect of air pollution. As well as acid rain, also I believe that loss of the ozone layer should be an effect of air pollution. I believe that volcano eruptions should be an cause of air pollution
I believe that smog reducing filters should be in the prevention box, as well for using electric cars.