Question

find the missing measurements for each circle. the radius of the circle is 10.5 cm, and point c is the center. find the length of the diameter and the approximate circumference of the circle.

Explanation:

Step1: Recall the relationship between diameter and radius

The diameter $d$ of a circle is twice the radius $r$, i.e., $d = 2r$. Given $r=10.5$ cm, then $d=2\times10.5$ cm.
$d = 2\times10.5=21$ cm

Step2: Recall the formula for the circumference of a circle

The formula for the circumference $C$ of a circle is $C=\pi d$. Using $\pi\approx3.14$ and $d = 21$ cm, we have $C\approx3.14\times21$ cm.
$C\approx3.14\times21 = 65.94$ cm

Answer:

Circumference: $65.94$ cm
Diameter: $21$ cm