Question

how to do this question ​

Answer 1

OA is the radius =r
AC is the diameter =2r
therefore option(A)is correct

Answer 2

Heya mate.....

The correct options from these all are (A)

Because in 1st it asked about the formula which is (c) pie r + 2r

Then in 2nd it asked about the length of OA which is radius so it is r means (b)

Then in 3rd it asked about the length of AC which is diameter so it is 2r means(a)

Hope it helps uhh