The concern in this item is for Maria to increase the size of her sample enough for her to make a conclusion out of those who have been interviewed. In order to do so, instead of doing the interview all alone, it would have been better for Maria to hire people to do the interview in parallel. She may work out the number of the people needed to become interviewers. Also, instead of doing the interview, she may opt to do it in a written form to allow the interviewee to just jot down the answers. She should however, make the question simple and much easier to understand.
