The half life for the radioactive decay of rubidium- to strontium- is years. suppose nuclear chemical analysis shows that there is of strontium- for every of rubidium- in a certain sample of rock. calculate the age of the rock. round your answer to significant digits.

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.