(a) How many ways can a store manager arrange a group of 1 team leader and 3 team workers from his 25 employees? (b) A state's license plate has 7 characters. Each character can be a capital letter (A - Z), or a non-zero digit (1-9). How many license plates start with 3 capital letters and end with 4 digits with no letter or digit repeated? (c) How many binary strings of length 5 have at least 2 adjacent bits that are the same ("00" or "11") somewhere in the string?