Problem $4(10$ points$)$

$($a$)$ How is a thermal symmetry boundary condition expressed mathematically? $d\frac{T}{d}x=0q=0$

$($b$)$ Consider a uniform wall $($constant thermal conductivity$)$ with internal heat generation. Each side of the wall experiences an equal convection environment $($same ambient temperature and convection coefficient$).$ Is it possible for part of the heat generated in the left half of the wall to leave the wall through the right wall face? Justify your answer and develop a supporting sketch. NO; ENERGY NOVES FROM Hor to cous

$($c$)$ What is the physical significance of the Biot number? Is the Biot number more likely to be larger for highly conducting solids or poorly conducting ones? Explain.