Choose all of the following scenarios below that contain biased samples. 1. Kelly wants to estimate the mean number of calories consumed by students at her school. She collects data from randomly selected individuals in the cafeteria for breakfast.
2. To estimate the ethnic background distribution of residents of her town, Deborah collects data from 1000 randomly selected town residents by using a random number generator.
3. To estimate the mean amount of money spent on clothes per week by mall shoppers, Paul collects data from every 10th person entering a clothing store at the mall.
4. Homer wants to estimate the mean grade point average of students at his school. He collects data by recording the grade point average of every 25th student on the list of students after a randomly selected first student.