<h3>
Answer: 18pi</h3>
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Explanation:
The area 81pi square meters leads to the radius 9 meters
Use the formula A = pi*r^2 to see why this is the case. You plug in A = 81pi and solve for r to get r = 9.
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Once you know the radius, you can determine the circumference C
C = 2*pi*r
C = 2*pi*9
C = 2*9*pi
C = 18pi
The circumference is the perimeter, or distance, around the circle.
<u>Given</u>:
Given that the measure of ∠CDR = 85°
We need to determine the measure of
and 
<u>Measure of arc RC:</u>
Since, we know that if a central angle is formed by two radii of the circle then the central angle is equal to the intercepted arc.
Thus, we have;

Substituting the values, we get;

Thus, the measure of
is 85°
<u>Measure of arc CBR:</u>
We know that 360° forms a full circle and to determine the measure of arc CBR, let us subtract the values 360 and 85.
Thus, we have;

Substituting the values, we have;


Thus, the measure of
is 275°
Each is 7 long and the whole piece is 56 so we can make 8 down the length and each is 1 wide and the whole things is 3 so that makes 3 across. we multiply these to get 8*3= 24
You could do 33, 36, 39, 42