Final answer:
The sentence that should be added after sentence 6 to move the plot forward is: 'Once I arrived, I quickly learned that my job would also entail wiping tables, mopping floors, and washing dishes.'
Step-by-step explanation:
The paragraph is from a personal narrative. It depicts the protagonist's excitement on her first day working as a waitress at Pete's Pizza Haven. To effectively move the plot forward, the sentence that should be added after sentence 6 is: O Once I arrived, I quickly learned that my job would also entail wiping tables, mopping floors, and washing dishes. This sentence introduces a development in the plot by showing what happens after the protagonist leaves her house and arrives at her new job.
Learn more about Plot development in a personal narrative