Please choose the correct ending to complete the given sentence: Food and Entertaining: [header] How to refrigerate foods safely [title] Avoid packing your refrigerator tightly. [step] Packing loosely allows the cold air to circulate. [title] Use an appliance thermometer to monitor the real temperature inside your refrigerator and your freezer.

Ending1: [step] If your refrigerator is freezer-safe but you have a thermometer, it will give you a very accurate reading. [title] Use a freezer folder to protect your food from dust, chemicals, and other debris. Ending2: [substeps] The refrigerator should be at 40 ° f (4 ° c) or below, but above 32 ° f (0 ° c). Your freezer should stay at 0 ° f (- 18 ° c). Ending3: [step] You can also use an ice cream scoop to decide on your fridge temp. If you want a thermometer that you can use while cooking, want to make sure that you only leave your refrigerator open for about 15-30 minutes. Ending4: [step] Boiling water can kill many chemicals that are stored in cold foods. If your refrigerator is currently cold, keep an electronic thermometer inside the refrigerator or freezer.

Answer format: ending1/ending2/ending3/ending4