Question

1. 15 cm. perimeter (terms of pi) perimeter (number)

Explanation:

Step1: Recall the formula for the circumference of a circle

The formula for the circumference (perimeter of a circle) is $C = 2\pi r$ or $C=\pi d$, where $r$ is the radius and $d$ is the diameter. Given $r = 15$ cm, then $d=2r = 30$ cm.

Step2: Calculate the perimeter in terms of $\pi$

Using $C=\pi d$, substituting $d = 30$ cm, we get $C = 30\pi$ cm.

Step3: Calculate the numerical - value of the perimeter

Taking $\pi\approx3.14$, then $C=30\times3.14=94.2$ cm.

Answer:

Perimeter (terms of Pi): $30\pi$ cm
Perimeter (number): $94.2$ cm