Hi alexander it is very true air pollution is only caused by human activity
Answer:
Hello your question has some missing parts attached below is the complete question
answer : 4 μm
Explanation:
since the scale bar works the same way as a scale on a map , each bar will therefore represent 1 μm and the mature parent cell's is about 4 times the labeled value hence the Mature parent cell diameter will approximately be : 4 μm
<u>Answer:</u>
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All the waves are pertubations that propagate (transport) energy.</h2><h2>
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Nevertheless, they have some differences:
1. Light waves are<u> electromagnetic waves</u>, while sound and water waves are <u>mechanical waves</u>, this is the first and principal difference.
2. Electromagnetic waves can<u> propagate in vacuum</u> (they do not need a medium or material), but mechanical waves obligatory need a material to propagate
3. Light waves are always <u>transversal waves</u>, this means <u>the oscillatory movement is in a direction that is perpendicular to the propagation</u>; but mechanical waves may be both: <u>longitudinal waves</u> (the oscillation occurs in the same direction as the propagation) or transversal waves.
4. Electromagnetic waves propagates at a <u>constant velocity</u> (Light velocity) while the velocity of mechanical waves will depend on the type of wave and the <u>density</u> of the medium or material.
5. <u>Mechanical waves</u> are characterized by the regular variation of a single magnitude, while <u>electromagnetic waves</u> are characterized by the variation of two magnitudes: the electric field and the magnetic field
6. <u>Water waves</u> are 2-dimensional waves, while the <u>light and the sound</u> are tridimensional spherical waves
7. Light waves <u>transports energy in the form of </u><u>radiation</u>, while mechanical waves t<u>ransport energy with </u><u>material</u>
Answer
given,
wavelength (λ)= 500 n m
thickness of film= 10⁻⁴ cm
refractive index = μ = 1.375
distance traveled is double which is equal to 2 x 10⁻⁴ cm
a) Number of wave


N = 2.91
N = 3
b) phase difference is equal to
Reflection from the first surface has a 180° (½λ) phase change.
There is no phase change for the 2nd surface reflection and there is no phase difference for the 2nd wave having traveled an exact whole number of waves.
net phase difference = 
= 270°
The continuous submarine mountain range which winds through all the oceans is called the mid-ocean <u>ridge.
</u>It is a form of a mountain which is found underwater, and it appeared there due to the movements of tectonic plates. It is responsible for the creation of new seafloor, meaning that the ground underwater changes constantly with the formation of these ridges. <u>
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