<human>: What is the best way to: to save money on ice and keep your food cold for longer

OPTIONS:
- Fill clean, empty milk jugs with water and chill it before leaving on your camp trip. Add the jugs to your cooler
- Fill clean, empty milk jugs with water and freeze it before leaving on your camp trip. Add the jugs to your cooler
<bot>: Fill clean, empty milk jugs with water and freeze it before leaving on your camp trip. Add the jugs to your cooler