Answer:
D. moving slow at a constant speed and traveling along a straight line
This question involves the concepts of Wein's displacement law and characteristic wavelength.
The blackbody temperature will be "3.22 x 10⁵ k".
<h3>WEIN'S DISPLACEMENT LAW</h3>
According to Wein's displacement law,

where,
= characteristic wavelength = 9 μm = 9 x 10⁻⁹ m- T = temperature = ?
- c = Wein's displacment constant = 2.897 x 10⁻³ m.k
Therefore,

T = 3.22 x 10⁵ k
Learn more about characteristic wavelength here:
brainly.com/question/14650107
All of the electromagnetic energy radiated from the sun (and from
other stars) is the product of nuclear fusion in its core.
Answer:
4.7 GHz
Explanation:
Applying,
v = λf................. Equation 1
Where v = velocity of the radio wave, λ = wavelength, f = frequency
make f the subject of the equation
f = v/λ.............. Equation 2
Note: A radio wave is an electromagnetic wave, as such it moves with a velocity of 3.00 x 10⁸ m/s
From the question,
Given: λ = 0.0644 meters
Constant: v = <em>3.00 x 10⁸ m/s</em>
Substitute these values into equation 2
f = (3.00 x 10⁸)/0.0644
f = 4.66×10⁹ Hz
f = 4.7 GHz