Energy drinks can be exchanged for one yuan at the store where they are bought.

One yuan for a bottle. Hal bought 1 bottle corresponding to the bottle cap at the price of 1 yuan. This is how the canteen was changed. There are instructions on the bottle of physical fitness, and the price of each canteen is different. For example, some people sell a bottle of 3 yuan, some people sell 3.5 yuan, and some people sell 4 yuan. Some businesses are unwilling to change, which is an act of deceiving consumers.