$3\mathrm{.}0$#$\_$#$\_$"What are the fundamental principles governing fluid mechanics in civil engineering, and how do they influence the design and analysis of hydraulic systems? Explain the concept of buoyancy and its relevance in civil engineering applications such as designing floating structures or water management systems. How does soil mechanics play a crucial role in foundation engineering, and what factors influence soil stability and bearing capacity? Discuss the basic principles of structural analysis and their significance in designing safe and efficient civil structures."