A 120‐m thick layer of air over a polluted city contains aerosol particles with diameters ranging from 1.0 to 1.7 m particles with a total concentration of 105 g/m3 , which is in excess of the 24‐hour PM2.5 threshold of 65 g/m3. (PM stands for Particle Matter, and the 2.5 subscript refers to particles 2.5 m in diameter or smaller.) The air inside this layer is constantly well mixed by winds, while the air above 120 m is perfectly clean and still. Because particles are heavier than air (particle density = 2500 kg/m3 whereas air density = 1.20 kg/m3 ), particles fall and settle on the ground, where they stick and are not re‐suspended. There is thus a net flux of particles out of the airshed. (a) (2 points) Does settling follow Stokes’ or Newton’s Law? (b) (3 points) What is the range of settling speeds for these particles? Check on the Reynolds number to ensure that you use the correct formula. (c) (5 points) How long doesit take for the atmospheric PM concentration at ground level to drop below the compliance threshold?

answer:

true

explanation:

answer:

// here is code in C++.

#include <bits/stdc++.h>

using namespace std;

//main function

int main()

{

  // variable

 int n;

 cout<<"enter a number:";

 // read the input

 cin>>n;

 // find the square root of the absolute value

 float square_root=sqrt(abs(n));

 // print the square_root

 cout<<"square root of "<<n<<" is: "<<square_root<<endl;

  return 0;

}

Explanation:

Read a number from user and assign it to "n".Then find its absolute value with abs() function.Then calculate the square root of the absolute value with sqrt() function.Print the square root of the number.

Output:

enter a number:-17

square root of -17 is: 4.12311

                                                         This is easy

                                                     sinserly Natalie 7 grader (this is not that hard)

answer:

careful measurement and analytical skills.

good attention to detail.

a good eye for design.

the creative and technical ability to turn designs into products.

the ability to empathise with patients.

communication and teamworking skills. please make me brainliest i need it one more time

Explanation:

I would say 47 or if u use a yard it would be 69 seconds! Happy braining! Also Nina is a god breian!

Explanation: