It should be 18, because despite of 3,14, because that's pi and radius is half of the diameter, so36 divide 2 is 18.
Diameter= 2 times the radius
2r=d
2r=10.2
R= 10.2/2
R=5.1
Therefore, the radius is 5.1 units which makes the answer choice C correct.
Hopefully, this helps!
The square on the hypotenuse is skew and impossible to visually validate. There's nothing to sum. It is a simple calculation to note that <span><span><span>32</span>+<span>42</span>=<span>52</span></span><span><span>32</span>+<span>42</span>=<span>52</span></span></span><span>, but its picture doesn't 'say' that the angle between the 3 and 4 sided square must be 90 degrees.
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