Explain this answer. The answer to the question is the tree below of it. I need an explanation of how and why the tree is drawn that way. Thanks

2. Draw the AST of the following postfix syntax expression, and rewrite the expression in prefix syntax. A subscript has been attached to each operator that shows the operator's arity. [The operators in this question and the next are not related to the operators in question 1.] ab$2 @1 3 u *1 v w $2 ~2 5 @1 ^3 #2 ANSWER prefix syntax: #e$ab^3~*u$vwe5