The student whose survey to find the pizza topping sixth-grade students prefer is likely not biased is; Julia
A sampling method is said to be biased of some members of a population are systematically more likely to be selected in a sample than others.
Now, in this case we are told that four students did a survey to find the pizza topping sixth-grade students prefer.
From the students methods, we can see that they all surveyed people but the one that is not biased would be Julia because the people she asked are the people that she wants to find the info about and as such they will be honest about it unlike the other three asking people that may likely utilized biased opinions.
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