Some crystals have rhombohedral structures. A rhombohe- dron is a parallelepiped in which all of the edge lengths are equal and each of the six faces is a congruent rhombus. Find the volumes of the...

Extracted text: Some crystals have rhombohedral structures. A rhombohe- dron is a parallelepiped in which all of the edge lengths are equal and each of the six faces is a congruent rhombus. Find the volumes of the rhombohedral crystals described in Exer- Turning a bolt with a wrench produces a torque vector that drives the bolt forward. The magnitude of the torque vec- tor is ||r||||F|| sin 0, where r is the vector along the handle of the wrench, F is the force vector applied to the handle of the wrench, and 0 is the angle between these two vectors. There- fore, the magnitude of the torque is ||r x F||. In Exercises 60 and 61, find the magnitude of the torque. Express each answer in foot-pounds. cise: 59. A rhombohedral crystal The torque vector torque F 59. Each side length is 2 cm, and the acute angles in each face measure 45°. (See the hint in the previous exercise.)