<span> In </span>transverse waves<span>, </span>particles<span> of the</span>medium<span> vibrate </span>to<span> and from in a direction perpendicular </span>to<span> the direction of energy transport. </span>
1) In the first case, the correct answer is
<span>A.Wavelengths measured would match the actual wavelengths emitted.
In fact, the stars are not moving relative to Earth, so there is no shift in the measured wavelength.
2) In this second case, the correct answer is
</span><span>A.Wavelengths measured would be shorter than the actual wavelengths emitted.
</span>in fact, since the stars in this case are moving towards the Earth, then apparent frequency of their emitted light will be larger than the actual frequency, because of the Doppler effect, according to the formula:

where f0 is the actual frequency, f' the apparent frequency, c the speed of light and vs the velocity of the source (the stars) relative to the obsever (Earth). Vs is negative when the source is moving towards the observer, so the apparent frequency f' is larger than the actual frequency f0. But the wavelength is inversely proportional to the frequency, so the apparent wavelength will be shorter than the actual wavelength.
Answer:

So then the difference of temperature across the material would be 
Explanation:
For this case we can use the Fourier Law of heat conduction given by the following equation:
(1)
Where k = thermal conductivity = 0.2 W/ mK
A= 1m^2 represent the cross sectional area
Q= 3KW represent the rate of heat transfer
is the temperature of difference that we want to find
represent the thickness of the material
If we solve
in absolute value from the equation (1) we got:

First we convert 3KW to W and we got:

And we have everything to replace and we got:

So then the difference of temperature across the material would be 