Answer:
Volume of a circle = approximatley 25.12
Step-by-step explanation:
1. Volume of a circle= 4/3*pi*radius
2. Radius equals 1/2 of diameter
3. 12/2=6
4. radius=6
5. 4/3*3.14*6=25.12
6. Volume of a circle = approximatley 25.12
Answer to part A: 11w^2+7z^2
Answer to part B: 14w^2+9w
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Explanation:
For part A, the expression 4w^2+7w^2+7z^2 has one pair of like terms. That pair is 4w^2 and 7w^2 which combine to 11w^2. You add the coefficients to get 4+7 = 11, then tack w^2 onto everything to say 4w^2+7w^2 = 11w^2
We cannot combine 11w^2 and 7z^2 as they aren't like terms. So we leave it as 11w^2+7z^2
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In part B, the like terms are 15w and -9w. They combine to 15w-9w = 6w. You can think of it like 15-9 = 6 then stick a 'w' to each term. We cannot combine the w^2 term with the w terms.
I think 8.0 is the answer
Lines that are parrellell presume to have the same slope.
So if we just calculate the slope of a function or a line we should be good.

Now put in the data from the coordinates of the points 

The form of a function now looks like:
From here we are no longer required to calculate anything more. Leave n alone.
The solutions are the equations of the form above.
That would mean:

Hope this helps.
Y = mx + b
m = (y2 - y1)/(x2 - x1)
y = (26,600 - 18100)/(20 - 10)x + b
y = 850x + b
18100 = 850(10) + b
b = 9600
R(x) = 850x + 9600