Suppose you found a material in which 12.5% of the original radioactive atoms were present. if the half-life is 47 years, how old is the material?

it is the most commonly accepted one

shield volcanos are angry and get mad over the smallest things so much that there heads erupt   pahoehoe and a'a lava. a composite volcano is the poller opposite of a shield volcano. its   peaceful thing and knows how to control its emotions.