As the word suggests, a quarter-sphere is a quarter of a sphere, and thus the volume of a quarter-sphere is a quarter of the volume of the sphere.
The volume of a sphere is computed as

So, the volume of a quarter-sphere is

In y=mx±b of slope-intercept form, the b is the y-intercept either positive or negative.
y=4x+12, in this case, 12 is your y-intercept!!
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I hope that helps you out!!
Any more questions, please feel free to ask me and I will gladly help you out!!
~Zoey
If you add all the numbers on the right together you get -35 then you divide by 5 which gives you the average of -7*F
D , because 28-9=21 and 21=x