Using the perimeter formula, first calculate the perimeter =3. 14* 10.

s=3. 14* 10*( 10- 1)=282.6cm^2

2. Solution: 2.8 decimeter = 28 cm

Diameter: = 62.8/3.14 = 20cm.

∵3. 14*(20/2)^2+62.8*28=3 14+ 1758.4=2072.4,

∴ At least 2080cm^2 is required.