A student planning a party has $20 to spend on her favorite soft drink. it is on sale at store a for $1.29 for a 2-l bottle (plus 10-cent deposit); at store b the price of a 12-pack of 12 fl oz cans is $2.99 (plus a 5-cent deposit per can). at which store can she buy the most of her favorite soft drink for no more than $20