The ozone layer is beneficial because it protects us from the ultraviolet (UV) rays from the sun. Without it, survival would be difficult. It is harmful by containing all the pollution and chemicals . That damages our lungs and causes chest pain, coughing,etc.
Answer:
A) Propagation of pressure fluctuations in a medium
B) air is the medium in which the wave is transported,
Explanation:
Part A.
A sound wave is a longitudinal oscillation of the molecules that forms in a material medium, they can be solid, liquid or gases, therefore the wave propagates in the same direction as the oscillation of the particles.
The most correct answer is:
* Propagation of pressure fluctuations in a medium
Part b
air is the medium in which the wave is transported, otherwise it cannot propagate
Answer:
The voltage across a semiconductor bar is 0.068 V.
Explanation:
Given that,
Current = 0.17 A
Electron concentration 
Electron mobility 
Length = 0.1 mm
Area = 500 μm²
We need to calculate the resistivity
Using formula of resistivity


Put the value into the formula


We need to calculate the resistance
Using formula of resistance



We need to calculate the voltage
Using formula of voltage

Put the value into the formula


Hence, The voltage across a semiconductor bar is 0.068 V.
Answer:
A the type of dog food because it was different and every other thing was the same.
"Constant velocity" is practically a definition for zero acceleration.