A Honolulu police detective testified that a Marine accused of murdering a prostitute visiting Hawaii was seen on surveillance video with the woman at his Waikiki hotel.  Later he was seen leaving with a large suitcase.  Detective Dru Akagi said the next morning, a cellular tower in Waianae picked up a signal from Marine Master Sergeant Nathaniel Cosby's cellular phone. And, the body of Ivanice "Ivy" Harris was found days later in some brush near Yokohama Bay.  An Article 32 hearing is under way at Marine Corps Base Hawaii in Kaneohe to determine if Cosby should be courtmartialed.  He's charged with unpremeditated murder, obstructing justice and patronizing a prostitute.  Akagi also testified that video shows Cosby meeting with Harris outside a Waikiki pub May 15th.  And, then the two are in an elevator at Cosby's hotel.  He told police he woke up and Harris was gone.