It's possible but it takes an experienced keeper and a strict broiler breeder diet to raise a Cornish Cross hen to maturity. Unless you are speaking of a True Rhode Island Red cock though, I am not sure what the goal of the cross would be. Anything with Cornish Cross blood in it will be a good meat bird but there's no reason to dilute the size further than necessary, and Production RIR cocks are skinny little things.
The offspring would be white with plenty of red leakage.