4. Determine whether each sample is biased or unbiased. Include your reason why for full credit! An employee of a phone company randomly chooses 80 customers to ask whether they are happy with their service.

5. Determine whether the sample is biased or unbiased. Include your reason why for full credit!
20 fans at a 49ers game are asked what their favorite team is.

4) Unbiased; 5) Biased

Step-by-step explanation:

4) states that the audience of the poll was "random" people meaning it's a good foundation of data as they weren't chosen for the employee noticing their specific affiliation with being overjoyed with the product (as the question doesn't say) or for not liking (have complaints about it) the product.

5) The audience of the poll is fans of a sports team--definitely biased because they'll say they love the 49ers being a fan for them. Leads to skewed results not representing a portion of a population accurately.

sorry, i can't understand your question. will later if you describe more clearly!

: )