==44*3. 14

= 138. 16cm^2

12/2 = 5cm

8/2 = 4 cm

(5*5-4*4)*3. 14

=9*3. 14

=28.26cm^2

50+2 = 52 cm

(52*52+50*50)*3. 14

=204*3. 14

=540.56cm^2

10/2 = 5cm

5*5*3. 14=78.5cm^2

10* 12-7805

= 120-78.5

=4 1.5cm^2

2*2*3. 14/2

= 12.56/2

=6.28cm^2

(6.28-2.28)*2/4

=4*2/4

2 cm