You are designing a travel plan application. A hotel booking step displays a form in which users select a hotel and enter thier check-in and check-out dates. The application calculates and then displays the cost for the hote at an extra cost. The application totals the cost for any selected options and adds that amount to the total room cost to equal the grand total, which is displayed in a field. Which two of the following properties would you use as the target properties ? (Choose two)