CONSTRAINED MODELS In this task you are going to be asked to design and/or build some three dimensional skeleton models given certain constraints. Whilst credit can be awarded for the actual construction of the models, it needs to be pointed out that full credit can be obtained without any such model actually being built, provided that the mathematical analysis necessary for the construction of such a model is clearly given. In particular, the quality of the model will not in general affect the grade. The three models under consideration are Model 1 A square based pyramid with the vertex directly above the centre of the square base. Model 2 A wedge. The horizontal base and vertical backplane of the wedge are both rectangular. Angle ABC is ninety degrees. Model 3 A tetrahedron. The base ABC of the tetrahedron must be a triangle right-angled at B. The vertex, V, must be vertically above B. Your task is to make, or imagine to make, at least one of the above models. You must explain all of your working and record all of your results and calculations. The constraints placed on you are that the model, or imagined model, MUST be made out of material with a total length of exactly one metre. You may use wire, straws, balsa wood or similar material that adds up to one metre, i.e. the sum of the edges of the models is exactly one metre.