Oxygen   Human being breathes oxygen equivalent to threecylinders.    Each oxygen cylinder on an average costs Rs 700, without subsidy.    So in a day one uses Oxygen worth Rs 2100 and for a full year it is Rs 7,66,500.    If we consider an average life span of 65 years; the costs of oxygen we use become a staggering sum of  Rs 500,00,000. Rs 50million.    All this oxygen is derived free of cost from the surrounding trees.   Very few people look at trees as a resource and there is rampart tree cutting going on everywhere which should stop.     Please pass this to your friends and care for trees.