Two tyrannosaur questions

["Norton, Patrick" <Patrick.Norton@state.me.us>]

A couple tyrannosaur inquiries:

I've seen some life restorations of T. rex that depict an external tympanic
membrane, similar to what is seen in some amphibians.  This seems curious to
me, since reptiles and birds both (to my knowledge anyway) have an open tube
leading to an internal typanum. Isn't it more likely that T. rex (or even
dinos in general) had an open ear tube rather than an amphibian-like
external membrane over the ear canal? I've seen them depicted both ways.

Also, the position of theropod arms and hands has been discussed a lot
recently, but not specifically with respect to T. rex.  If a T. rex were
standing still and holding its arms in a "relaxed" position, would its palms
more likely be facing the ground or facing inwards towards its midline?  I'm
familiar with Sereno's talk several years ago about theropods probably not
being able to pronate or supinate their hands, but am wondering if that
generalization is applicable to T. rex?

Thanks.

PTN