JALCULATOR
The half-life of Carbon-14 is 5,730 years. How many half-lives will it take for 3/4 of a given amount to decay, so that 1/4 of the Carbon remains?
half lives

if, i suppose that a bee stings me swinging my hand away from a bee. then that if, i persist patient when a bee or wasp areas on your surface to investigate a scent or to take h2o and i secreting heavily, the bug ultimately will move of its personal agreement. if i don't need to set for it to disappear, lightly and gently wipe it off with a part of the paper.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.