Final answer:
Standing waves in a rectangular swimming pool would appear as nodes and antinodes at fixed positions.
Step-by-step explanation:
Standing waves in a rectangular swimming pool would appear as nodes and antinodes at fixed positions. Nodes are points in the wave pattern where the wave undergoes minimum or no displacement, and antinodes are points of maximum displacement. The nodes would occur at each end of the pool while the antinodes would be in the middle.