Black has a four on row 7 — and the completing stone would also build a four on the diagonal, which on any other day would be forbidden stacking. Rule 9.7 settles it: a five overrules every forbidden pattern. Take the five and the game is over before the foul is even judged. This is why white must always count black's fives before counting black's fouls — the win check comes first.
Solve the remaining tasks to finish this lesson.