PORTLAND, PR.- The skeleton of a Tyrannosaurus rex will make its museum debut at the Oregon Museum of Science and Industry along the banks of the Willamette River. Museum President Nancy Stueber said the fossilized bones of a 40-foot-long predator dinosaur that weighed 7.5 tons and lived 66 million years ago will be on display beginning Dec. 17 through the end of summer 2010. Scientists haven’t settled on whether the animal was male or female, Stueber said. Known as Samson, the fossil was dug up in the 1990s in South Dakota. It has been in private hands since then, most recently purchased this fall by an anonymous buyer after a failed Las Vegas auction. It is among three T. rex skeletons with more than half the bones remaining, and its skull is well preserved, the museum said in a statement. A similar T. rex fossil sold for $8.3 million in 1997 and is now housed at the Field Museum in Chicago. That dinosaur, named Sue, is 42 feet