If mom is A plus can the dad be RH plus?

Yes, the mother being A+ and the father can still be Rh+.

The Rh factor is determined by a antigen present on red blood cells. Individuals with the Rh antigen are Rh-positive and those without are RH-negative. In this case, the mother being A+ simply means that she has type A blood and is Rh-positive, while the father can be Rh-positive as well.