Question

Find out the cirumference of diameter = 9 cm

Answer 1

Answer:

$r = 4.5 \\ area \: of \: circle \: = 2\pi \: r {}^{2} \\ so \: 2 \pi \times 4.5 \times 4.5 \\ = 2\pi20.25 \\ = 40.50\pi$