What do the symbols in parenthesis indicate?
cacl2(aq) + 2agno3(aq)) d ca(noà)2(aq) + 2agcl(s)
1.the catalyst used in the reaction
2. the number of atoms of each reactant and product
3. the physical state of each reactant and product
4. the number of units of each reactant and product

The symbols in parentheses indicate 3. the physical state of each reactant and product.
(aq) means aqueous, or liquid state, and (s) means solid state.
2 and 4 are definitely incorrect because there are no numbers in the parentheses. 

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.