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Answer with explanation:</h2>
Given : The diameter of the circle = 2r , where r is the radius.
Function notation for diameter :
If the value of r= 5 feet
Then , the diameter of the circle is feet = 2(5) feet = 10 feet
Hence, the diameter of the circle is 10 feet when the radius is 5 feet.
Also, area of circle : , where r is the radius .
Function notation for area :
For r= 5 feet
Hence, The area of the circle is square feet when the radius is 5 feet.
Also, the circumference of circle =
Function notation for circumference =
For r= 5 feet
Hence, The circumference of the circle is feet when the radius is feet.