To find the area of a circle- A= 3.14*(4 cm squared). ( The 4 cm is your radius. Half of the diameter.) After you square your radius you get 16cm squared. You then go onto multiply the 16 cm squared by 3.14 to get 50.24 cm squared.
To find the circumference of a circle- C= 2*(3.14)*(4cm). (Again the 4cm is your radius. Half of the diameter.) After you multiply the 2 and 3.14 you get 6.28. You then multiply the 6.28 by 4 cm to get 25.12 cm.
