Kreis und Kugel

Radius = r
Durchmesser = 2 ⋅ r
Umfang = 2 ⋅ π ⋅ r
Kreisfläche = π ⋅ r2
Kugeloberfläche = 4 ⋅ π ⋅ r2
Kugelvolumen
= 4/3 ⋅ π ⋅ r3