Odpowiedzi

2009-11-21T18:59:15+01:00
3000cm³ = 20cm * πr² |/20cm
150cm² = πr² |/π
47,77cm² =r² |√
6,911cm = r

r≈6,9 cm


1 5 1
2009-11-21T22:43:34+01:00
V = 3000 cm³ = 3 dm³
h = 2 dm
V = P_p * h
P_p = V/h
P_p = 3 dm³/2 dm
P_p = 1.5 dm²
P_p = πr²
r^2 = P_p/π
r = √(P_p/π)
r = √(1.5 dm²/3.14)
r = √(150 cm²/3.14)
r = √47.77
r = 6.91 cm