Answer: The control group is the part where you see what happens when you change a variable you want to study/examine. Basically, you need the control group because you need something to see what happens when you change something.
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It is b! the lithosphere is the crust and upper mantle
Answer:
Sometimes may cause involuntary responses like twitching
Explanation:
Answer:
A) receding from the earth
B) 
Explanation:
- A) receding from the earth
The wavelength went from 434.1nm to 438.6nm, there was an increase in wavelength (also knowecn as redshift due to the doppler efft), this increase is due to the fact that the source that emits the radiation (the distant galaxy) is moving away and therefore the light waves it emits are "stretched", causing us to see a wavelength greater than the original.
- B)

to calculate the relative speed we use the following formula:

where
is the speed of light:
is the wavelength emited by the source, and
is the wavelength measured on earth.
we substitute all the values and do the calculations:

the relative speed is: 
Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds. PLZ MARK ME BRAINLIEST