PRIVATE PRACTICE - "Past Tense" - An office election pits Sam and Naomi against each other to lead the practice, and ends with surprising results, while Addison treats a young Afghan girl who wants to hide her past, and Cooper's objectionable personal life catches up with his professional one, on "Private Practice," WEDNESDAY, OCTOBER 29 (9:00-10:01 p.m., ET) on the ABC Television Network. (ABC/ERIC McCANDLESS) PAUL ADELSTEIN, KaDEE STRICKLAND