In a ZONED SYSTEM should you split a large room between 2 ZONES to equal the number of vents between zones or should you always have the boundary run along a wall?

Usually the exterior windows and walls are the location of choice. Usually if you are doing a zone system you do the large room with a single zone since this is part of the reason for controlled zoning to start with.

Another homework question?

Could be. LOL

Umm, C) Clean the flame sensor. No, wait... B) Replace the.. . I should have studied for this...