You have done three different shell structure models and a space frame model. This reading exercise gives you an opportunity to reflect on any four of the structural challenges you noticed while doing the experiments with the models. Explain one challenge in each model exhibiting your structural understanding gained through reading the related content for the model from the textbooks suggested. Also explain how this challenge would be resolved in a fullscale real$-$life shell structure. Through neatly annotated sketches and notes, Explain the forces, structural challenges discovered during your experiments and and real$-$life solutions these.