Answer from cs61c-ei (Jing Chen 16669246) for Question 2
A programming language that forbids the use of recursion does not need to allocate frames on a stack. In a nonrecursive language, each procedure’s frame maybe statically allocated since only one invocation of a procedure can be active at a time.  

I did not take CS61a and learn Scheme, so I’m not sure how recursion works in that language.