This happens because the temperature at which oxygen changes from a gas to a liquid is about 13 degrees Celsius above that of nitrogen. The oxygen can be seen dripping from the can just as on a humid day you can see drops of water condense and drip from a can you take from the refrigerator.
Though you technically can join the military up to age 42, if you're 35 or over you'll need an age waiver if you've never been in the military before.
Best Answer: you may join the royal marines at the age of 17 but even after your training you will not be permitted to go to a warzone till your 18. (not a problem if you join as an officer as your training is longer than a year.).