When shopping online, you select items and add them to a shopping cart. Duplicate items are permitted in a shopping cart, as you can purchase multiples of the same item. You also can remove an item from a shopping cart, if you change your mind about buying it. The shopping cart can show its current contents with their prices and the total cost of these items. Design the ADT item and shopping cart.

Arnold rossiter is a 40-year-old employee of the barrington company who will retire at age 60 and expects to live to age 75. the firm has promised a retirement income of $20,000 at the end of each year following retirement until death. the firm's pension fund is expected to earn 7 percent annually on its assets and the firm uses 7% to discount pension benefits. what is barrington's annual pension contribution to the nearest dollar for mr. rossiter? (assume certainty and end-of-year cash flows.)