A. A prescription order page with a list of available prescriptions sent from the customer's health care provider. When the user opts to fill one or more prescriptions, the cost summary updates.

B. A flight booking page where customers can adjust the location and date of the departure and return flights. The ticket prices recalculate after the customer chooses the "recalculate price" option.

C. A restaurant reservation page in which the user chooses a reservation time and the system returns the number of available tables.

D. A purchase order request page with a summary of items. The order total price updates after the customer changes a quantity.