avem 4 semicercuri a caror lungime = lungimea a 2 cercuri cu raza 10:2=5
a)
Lgard=2×2πr=2×2×5π=20π≈62,82 m
b)
Apatrat=10²=100 m²
Asemicercuri =4× πr²/2=2πr²=2×5²×π=50π
Ateren=50π+100=50(π+2) m²
Ateren=50π+100=50×3,141+100=157,05+100=257,05 m² =25705 dm²
c)
25705 dm² :25 dm²/trandafir=1028,2 trandafiri
