Question 2 (6 marks) A Bauman string is a string of letters that satisfies the following two conditions: Each letter in the string is A, B, C, D, or E. No two adjacent letters in the string are the same. For example, AECD and DBCEC are Bauman strings of length 4 and length 5, respectively. However, ABBC and DAEEE are NOT Bauman strings. .