First Question
circumference = pi * diameter
diameter = circumference/pi = 94.2 in./3.14 = 30 in.
The wheels have a 30-inch diameter.
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Second question
The area of a circle: area = pi * r^2
radius = diameter/2 = 94.2 in./2 = 47.1 in.
area = pi * r^2 = 3.14 * 47.1 in. * 47.1 in. = 6966 in.^2
Answer: 6966 in.^2
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Third question
The piece of felt has a width equal to the diameter of the wheel. The length has to be the same as 4 diameters.
4 * 94.2 in. = 376.8 in.
Answer: 376.8 in.