2. L = 2πR = 2*3,14*14 = 87,92 см
3. R = L/2π = 18,84/(2*3,14) = 3 см
4. S = πD²/4
D = √(4S/π) = √(4*28,26/3,14) = √36 = 6 см
5. Фигура - половина окружности
S = πR²/2 = 3,14*100/2 = 157 кв.см.
6. 100%-30%-40% = 30%
30*30% = 30*0,3 = 9 га
8. 17,1:9,4 ≈ 1,819 ≈ 2