The given circle has a diameter of d=4.2 m.
It is required to find the circumference and area of the circle.
Recall the formula for the circumference of a circle with diameter, d:
[tex]C=\pi d[/tex]
Substitute d=4.2 into the formula:
[tex]C=\pi(4.2)\approx13.2\text{ m}[/tex]
The radius of a circle is one-half of the diameter. It follows that:
[tex]r=\frac{d}{2}=\frac{4.2}{2}=2.1\text{ m}[/tex]
Recall that the area of a circle with radius, r is given as:
[tex]A=\pi r^2[/tex]
Substitute r=2.1 into the formula:
[tex]A=\pi(2.1)^2=4.41\pi\approx13.9\text{ m}^2[/tex]
The circumference is about 13.2 m.
The area is about 13.9 m².
