How long can a person live without food and water or air?

Humans can scale the highest mountains and live in the harshest deserts. But we all live precarious lives: ones not far from death if we lose access to simple things like water, food, or even sleep.How long can we survive without the basics? Every person and situation is different, though the "rule of threes" gets at the desperate nature of what our bodies need: three minutes without oxygen, three days without water, three weeks without food.