Can honda EB2800 run A/C and fridge?
You are probably just going to have to try them.  Technically, as long as the frig is a somewhat standard size, it should handle them both.  Get the generator running good for a couple of minutes.  Using heavy duty cords that are no longer than necessary, plug in the A/C unit first.  How well does the generator handle it. Has the voltage dropped any?  Has the RPM dropped any significant amount?  If things seem ok then plug in the second unit.  See if it will frig run.  Do the checks on the generator again.  Try to get a wattage and amp draw on both units and work the math.  The one place where you will more likely have trouble, which is unlikely to happen, they both try to start at the very same time.  Good Luck. P.