A sample contains 9,000 particles of the original isotope for every 63,000 particles of the daughter isotope. The half-life of the original isotope is 19 years. Find the age of the sample.

There is one s orbital, and there are three p orbitals, five d orbitals, and seven f orbitals. thus, the answer is b. do not confuse the number of orbitals in a subshell with the number of electrons the subshell can hold. each orbital can hold two electrons, so the capacity of an nf subshell is 14 electrons.