Edit: I thought you said "determine" rather than "know", answered accordingly below. Of course they don't "know", that's not a helpful question. The same way

Edit: I thought you said "determine" rather than "know", answered accordingly below. Of course they don't "know", that's not a helpful question. The same way everyone does when trying to solve this problem systemically (vs individually), by making imperfect decisions and leaning on categories. My UVC lamp was delayed. I think that's more important than someone else's "third month" bunker food, but what are you going to do.