Is someone walking up to you from behind? A friend is walking up to you from behind. What three observations would help you predict when they would reach you?

Three things i will observe are :

The sound of their movement when approaching meThe frequency of their foot stepThe distance they are away from me

Explanation:

In my opinion, the three points highlighted above can go a long way to help predict how soon or when they would reach meThe sound of their foot steps will determine how far or close they are from from me, if the sound is loud they are closest, if it is low then they are at a distance father.The frequency of their foot steps tell me about the speed with which they are approaching me, if the frequency is high, then they will approach sooner and vice versaThe distance they are way from me can help estimate when they would reach me, though still dependent on items  one and two above.

answer: carbon 14 can only be used to determine the age of the organisms that were once living, and igneous rocks are non living.

explanation:

carbon 14 dating is used to determine the age of the sample by estimating the amount of carbon 14 present in the sample and then comparing it with a reference standard.carbon 14 is a isotope of carbon which is radioactive and unstable. carbon 14 is assimilated by all plants and animals throughout their life from carbon dioxide. however, one the organisms die they stop this assimilation and the carbon 14 content starts to decrease.by knowing how much of carbon 14 is left in an organism after his death, one can estimate the age of the organism. the materials whose age can be estimated by carbon 14 method are the organic compounds. however, some inorganic compounds such as aragonite   shell can also be dated.however, if we consider the igneous rocks it is a non living component which never accumulated carbon 14 in it and thus, we cannot use carbon 14 dating method to estimate its age.