1.28/100*25=7
2.36/100*25=9
3.68/100*25=17
4.100/100*25=25
5.232/100*25=58
6.360/100*25=90
36•42-22•36\72•16+34•72=36*(42-22)/72*(16+34)=20/2*50=20/100=0.2
Sкольца = S2-S1
S = п * R * R
S1 = 3,14 * 16 *16 = 803,84 м2
S2 = 3,14 * (16 + 5) * (16 + 5) = 1384,74 м2
<span>Sкольца = 1384,74 - 803,84 = 580,9 м2</span>