Matilda asked 20 random people in the street if they would like to discuss what they want to do during the summer break. seven of them said yes.
how is this sample biased?
(1)she should have asked more people.
(2)the people who chose to participate might not be similar to the people who didn’t.
(3)the number of people who agreed was too small.
(4)she should have asked girls only.