its D
i hope this helps to future test takers. i took the test and had to retake it because their wasn't an answer
Answer:
m = 0.51[kg]
Explanation:
Potential energy is defined as the product of mass by gravity by height.

where:
Epot = potential energy = 15 [J]
m = mass [kg]
g = gravity acceleration = 9.8 [m/s²]
h = elevation = 3 [m]
Now replacing:
![E_{pot}=m*g*h\\15=m*9.8*3\\m = 0.51[kg]](https://tex.z-dn.net/?f=E_%7Bpot%7D%3Dm%2Ag%2Ah%5C%5C15%3Dm%2A9.8%2A3%5C%5Cm%20%3D%200.51%5Bkg%5D)
A standing wave is the result of a reflection.
Answer:
The radiation pressure of the light is 3.33 x 10⁻⁶ Pa.
Explanation:
Given;
intensity of light, I = 1 kW/m²
The radiation pressure of light is given as;

I kW = 1000 J/s
The energy flux density = 1000 J/m².s
The speed of light = 3 x 10⁸ m/s
Thus, the radiation pressure of the light is calculated as;

Therefore, the radiation pressure of the light is 3.33 x 10⁻⁶ Pa.
Answer:
the soild material is allowe to settle into a sludge layer the remaining waste water undergoes a secondart treatment that uses bacteria to break down organic matter
treat water is left to sit while particles settle out, with settle d particles being added to sluudge,
water is disinfeted
Explanation: