Apharmacy wants to survey its customers to find out which brand of toothpaste they prefer.. . which survey methods are likely to be biased? . . choose all answers that are correct.. . a.. . a survey is sent to the customers who are on the pharmacy’s frequent buyer list.. . b.. . one hundred people from the pharmacy’s customer list are selected at random, called on the phone, and asked.. . c.. . those customers who buy toothpaste with a coupon are selected, and the toothpaste brand they purchased is recorded.. . d.. . every 10th customer who enters the p