Answer: r = C/(2pi)
This is the same as writing 
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Explanation:
pi is some number (approximately 3.14) which means 2pi is also some number (roughly 6.28)
Saying c = 2pi*r means we have 2pi times r, and the result is the circumference c. To isolate r, we'll undo the multiplication. We'll undo it by dividing both sides by 2pi like so
C = 2pi*r
C/(2pi) = r
r = C/(2pi)
in which we can write it like 
So whatever C is, we divide it over 2pi (aka roughly 6.28) to get the radius.
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Extra Info (Optional Section):
As an example, let's say the circumference of the circle is 628 feet. This means the distance around the circle is 628 feet. So C = 628 would lead to...
r = C/(2pi)
r = C/(6.28)
r = 628/(6.28)
r = 100
So the radius would be roughly 100 feet.
Answer:
I'm pretty sure that it's -i
Let same number of hours = x,
since the salary earned is also the same, then
Salary of supervisor A = $25x
Salary of supervisor B = $20(30)+$30(x-30)
Equating
25x=600+30(x-30)
30x-25x=900-600
5x=300
x=60 hours
Check:
Salary of supervisor A = 25*60=1500
Salary of supervisor B = 20*30+30*(60-30)=600+900=1500, ok.
We know that
area of circle =pi*r²
for r=4 ft
area=pi*4²------> 16*pi ft²
<span>the shaded sector of the circle represent 3/4 of the total area
so
3/4*16*pi-----> 12*pi ft</span>²
the answer is
12*pi ft²
(x^2 - 1)(x^6 + x^4 + x^2) =
x^2(x^6 + x^4 + x^2) - 1(x^6 + x^4 + x^2) =
x^8 + x^6 + x^4 - x^6 - x^4 - x^2 =
x^8 - x^2 <==