Question

I need some help on this paper, it’d be nice if someone could help. <3

Answer 1

what math is this?

Explanation:

Answer 2

For the first:

R:half of the diameter:2

D:4

C:diameter×pi

`\pi \ \: diameter`

4×3.14=12.56

A:

`\pi \: {r}^(2)`

3.14×4=12.56

The amswers are same.