Drumlin were formed during the Wisconsin glaciation. Drumlins are found at Tiksi, Sakha Republic, Russia. Extensive drumlin fields are found in Patagonia, for example near Punta Arenas Carlos Ibáñez del Campo Airport and on Navarino and Gable Island in the Beagle Channel. In 2007, drumlins were observed to be forming beneath the ice of a West Antarctic ice stream. French River outburst floods: https://www.youtube.com/watch?v=7L2rnpWE3jA Drumlin A drumlin, from the Irish word "droimnín" ("littlest ridge"), first recorded in 1833, and in the classical sense is an elongated hill in the shape of an inverted spoon or half-buried egg formed by glacial ice
Elongated triangular orthobicupola = 4 tetrahedra, so total we have 20 tetrahedra. What is the volume of a tetrahedron? Construct a tetrahedron having vertices in common with alternate vertices of a cube (of side formula_1, if tetrahedron has unit edges). The 4 triangular pyramids left if the tetrahedron is removed from the cube form half an octahedron = 2 tetrahedra. So formula_2 The hexagonal prism is more straightforward. The hexagon has area formula_3, so formula_4 Finally formula_5 numerical value: formula_6 The elongated triangular orthobicupola forms space-filling honeycombs with tetrahedra and square pyramids.<br> Elongated triangular orthobicupola In geometry, the elongated triangular orthobicupola is one