What is a hot path? Why is it significant? Under what circumstances can a JIT compiler expand virtual methods in-line? What is deoptimization? When and why is it needed? Explain the distinction...

What is a hot path? Why is it significant? Under what circumstances can a JIT compiler expand virtual methods in-line? What is deoptimization? When and why is it needed? Explain the distinction between the function and expression tree representations of a lambda expression in C#.