Which unit would be used to measure the amount of matter in an object?

Typically Grams or Kilograms are used to measure mass. On an atomic scale you would use Au for measuring atoms.

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.