The same way YOU hold your breath under water. Not breathing.
they can hold there breath for up to 40 to 50 minutes
It's harder to hold your breath because there's no AIR & OXYGEN and 'cause in water if you hold your breath too long you die, but if you hold your breath in the air and if you think you are...
you have to grow gills or eat a computer
That depends on your lung capacity. The world record is 19 minutes and 21 seconds.
yes