In processing a prefix expression, which part of the process was recursive? Calculating the value of the prefix expression Determining the complexity of the prefix expression Checking the syntax of the prefix expression Finding the end of a prefix expression What can be done to an infix expression to make it easier to evaluate in a program? Nothing, they are always very complex to process Add all of the parenthesis making it a fully parenthesized infix expression Convert to prefix, then to postfix, then it can be easily evaluated Perform backtracking.