What size serpentine belt?

Thanks a lot. My mother is in the UT Medical Center with hours or days left. I have been driving the ten hours round trip twice a week in my car. We are going to take the motorhome and leave it there so that at least we will have a regular place to stay when we get there. When this is all over I will drive it back home. The last thing I can deal with right now is being broken down some place.