Before submerging, Mark does not take a breath and after expelling all the air in his lungs, he can swim underwater for 2 minutes and 20 seconds.
Mark does not take a breath. This is before submerging. He can swim underwater for 2 minutes. This is before submerging. He can swim underwater for 20 seconds. This is before submerging. He is expelling all the air in his lungs. This is before submerging.