Dia. 6-1-6 shows that the result under area rules III is the same if
Black passes after White 274.
Dia. 6-1-6 (274 - 289) pass: 275
In this game, after White 274 there are an even number of empty points
on which either player could play without profit or loss, including the
point in the ko (which is similar to a neutral point, because Black
cannot win the ko). Because this number is even, the last competitive
move can be made at White 274 under both territory rules I and area