Children below the age cannot be employed in hazardous job.

If you are asking for the age of how old until you can do a hazardous job, i'm pretty sure the answer is 18 years old. You have to be 18 in order to do a hazardous job. If you are under that age, you cannot. But i have heard that you can do a job that is not hazardous at the age of 16 or 17. I hope this helped :)

You can drink laxative, or  do this exercise when you are sitting in the bathroom on the toilet. to relieve  constipation  fast or in about 1 minute, pinch your nose after your usual exhalation. start holding your breath. but do not mouth breath during this just hold your breath. 

Clean air provides nitrogen