Answer:
meters
Step-by-step explanation:
Recall to find the circumference of a circle the formula is 
or 
.
We start by substituting 4.7m for r in the second circumference formula.
. We input this value of r into the area formula.
The terms in the sum are given by the sequence
We have
for all 
, and the series 
clearly diverges, so 
must also diverge.
Split the object then find the 2 areas then subtract
Answer: <span>A square inscribed in a circle.
</span>
Justification:
Note that by making two perpendicular lines that intersect each other in the center of the circle, he obtains 4 equidistant points on the circumference.
So, joining each pair of neighbouring points, the image will reveal 4 congruent sides joining at right angles (90°). This is the image of a square with the four vertices on the circumference.
Answer: $56.50
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(instead of dividing each of them individually and them subtracting them one by one, combine them together as a fraction first and then subtract)
80 - (68/5 + 51/2 + 22/5)
= 80 - (136/10 + 255/10 + 44/10)
= 80 - (435/10)
= 80 - 43.5
= 56.5
He saved $56.50 on that
