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Once he clicks, Rob is redirected to a Bill Page which shows him the details of the rent bill. To his surprise, one of his housemates, Umbridge, who goes by the username "buddyU", has already paid her share of the bill. Rob knows that he can afford to pay his share of the rent bill now and, not wanting to be outdone by Umbridge, he decides that he will pay the bill now. Rob writes a check to the landlord and goes downstairs to put it in the landlord's mailbox. When he returns to his computer, Rob clicks on the "Pay Bill" link at the bottom of the rent bill. This updates his payment status to "paid". Satisfied, Rob logs off of the site.
Analysis 2
Learnability
Visibility
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