See [ss RateUnit].

- [ex 001 "The cost is $10 [p en/per RateUnit] item." "[exref 001 RateUnit]"]

- [ex 002 "A fuel efficiency of 40 miles [p en/per RateUnit] gallon (of gas)" "[exref 002 RateUnit]"]

- [ex 003 "Pizza is sold [p en/by RateUnit] the slice." "[exref 003 RateUnit]"]

- [ex 004 "They charge [p en/by RateUnit] the hour." "[exref 004 RateUnit]"]