Wartehäuschen mit Materialbedarf `20::m^2`, quadrat. Seitenflächen, Volumen maximal:

agraph width=700; height=645; xmin=-4.5; ymin=-0.5; xmax=10.5; x = 7; // Abstand zwischen den y-Achsen tickLineY([7,-1], [7,14]); for (var u = -2; u < 2.01; u += 1) text([u,0], u.toFixed(0), "below"); for (var u = -2; u < 2.01; u += 1) text([x+u,0], u.toFixed(0), "below"); moveM([1.5,11.5]); text([0.1+7, 12.7],"`V(u)=10u-u^3`", "right"); text([-4,7], "u ="); text([-4,6], "b ="); text([-4,5], "V =" ); strokewidth=2; endagraph