32. The research question for an undergraduate research project was whether hearing-impaired customers were treated differently by store clerks than non-hearing-impaired customers. There were 20 customers, 10 of whom were hearing impaired. The customers were sent in pairs into stores. The hearing- impaired pairs used sign language to communicate with each other and the non-hearing-impaired pairs entered stores speaking English to each other. The subjects consisted of 77 salesclerks in 27 stores (from 175 stores) in a large shopping mall. The response variable was the time that elapsed from when the pair entered the store and made eye contact with the salesclerk until the clerk approached and offered assistance. Describe how you would design the rest of the experiment.