This lecture discusses the selection of mesh size for structural analysis using Cedrus software. The instructor addresses common questions regarding optimal mesh size, emphasizing the importance of accuracy in results. The lecture begins with a review of previous discussions on mesh size, where the instructor shares personal experiences and choices made during analysis. The instructor explains that while a mesh size of 0.5 meters was chosen, it is crucial to analyze how different sizes affect results. The discussion includes comparisons of various mesh sizes and their impact on positive and negative moments in structural elements. The instructor highlights that smaller mesh sizes may not always yield significant changes in results, but they should be chosen carefully, especially in relation to the thickness of the slab. Additionally, the lecture covers the implications of support types on structural calculations, urging students to consider the most unfavorable scenarios for accurate results. The session concludes with advice on ensuring consistency in results and the importance of thoughtful analysis in structural engineering.