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Given an input string, complete a helper method that extracts the vowels and returns the string of the vowels in the input string recursively. All strings are lowercase. Do not use any loops or regular expressions. Test case 1: extract Vowel ("i love you 3000") Test case 2: extractVowel ("aiueo"). "aiueo" "ioeou" Given methods: 1. public static String extractVowel (String str) { return extractVowelHelper (str, 0, ""); 2. 3. } 4. 5. 6. 7. } private static boolean isVowel (char c) { return c == 'a' || c == 'e' || c == '1' || c == '0' || c == ''; For example: Test String input "i love you 3000"; System.out.println(extract Vowel (input)); String input "aiueo"; System.out.println(extractVowel (input)); Answer: (penalty regime: 0, 15, 30, ... %) Reset answer Result ioeou aiueo For example: Test String input "i love you 3000"; System.out.println(extract Vowel (input)); Result ioeou String input = "aiueo"; aiueo System.out.println(extract Vowel (input)); Answer: (penalty regime: 0, 15, 30, ... %) Reset answer 1 private static String extract VowelHelper(String str, int start, String vowels) { // base case 2 3 4 5 6 7 8 9 10 |} Check // recursive step