calculateLetterGrade(96) returns a value because it is assigned to a variable. submitFinalGrade does not return anything.

A global variable can be used anywhere in the program. A local variable only exists inside the function where it is created.

Global: stateTaxRate, federalTaxRate. Local: wages, totalStateTaxes, totalFederalTaxes, totalTaxes.

The program crashes because sum is a local variable inside the function and does not exist outside of it.

True — all prompt input is a string.

parseInt()

parseFloat()

It uses = instead of == or ===. = assigns a value instead of comparing.

The value of x will be 20.

Stepping over runs a function without going inside. Stepping into goes inside and shows each line running.