Question

circumference = when (radius given and = when diametwr is given​

Answer 1

Answer:

$2\pi r$  and  $\pi D$ are the answers respectively.

Step-by-step explanation:

We are told to find the circumference of the circle in 2 cases

1. Radius is given
2. Diameter is given

Let us assume that any circle with center O and radius r is given

Then we know that  the diameter D is given by 2r

i.e., D=2r

Now the Circumference of any circle is generally given by $2\pi r$

so the first answer is done

For diameter if we can do

$C = 2\pi r\\or, C =2r\pi$

Substituting 2r=D

we get $\pi D$

Therefore second answer is also done.