| Description | Slide shows two rows of black and white symbols; one row assigned to PI, the other FI.
The sequence of PI symbols is as follows: [black square], [blank square], X, [blank square], Y.
The sequence of FI symbols is as follows: [black square], three [blank squares], [black square], Y, [blank square], Y.
There is an arrow leading from the 'X' of the PI row to the middle of the FI row of symbols. |