Argue whether or not you believe using a sample of students from your school's cafeteria (you recruit the next 100 people to visit the cafeteria to participate) may or may not yield biased estimates based on the variable being measured/research question being investigated in each of the following situations.

a. Using the proportion of students with Type O blood to learn about the proportion of U. S. adults with Type O blood
b. Using the proportion of students who eat fast food regularly to learn about the proportion of U. S. college students who eat fast food regularly