The area of a square is length times width. Therefore, based on your question: 4 cm x 4 cm = 16 sq cm. So the area of your square is 16 square centimetres.

Each square has an area of 1 cm square, for 4 squares altogether area is 4 cm square. Or we can say we have a big square 2cm by 2cm, whose area is 4 cm square.

O = pi*D cm = 3,14 * 3,5 cm = 11 cm The circumference from the inside square is Li = 4*(Root from (2*(D/2)square))= 4*Root 2,47 =9,89 cm. The circumference from the outside square is Lo = 4* D = 14 cm.