【单选题】Which of the following is a valid function header for the getArea function? The function returns a double number and does not have any formal parameters.
【多选题】Given an EL function foo, in namespace func, that requires a long as a parameter and returns a Map,which two are valid invocations of function foo?()
【单选题】Given an EL function foo, in namespace func, that requires a long as a parameter and returns a Map, which two are valid invocations of function foo?()