Al(NO3)3(aq) + 3NaOH(s) --> Al(OH)3 (s) + 3NaNO3 (aq)
The precipitate here is Al(OH)3 (s), since the solid reactant is the precipitate in the aqueous solution. Usually, it is okay to assume in basic chemistry that the transition metal is going to be part of the compound that is the precipitate, especially in an acidic salt and a strong base reaction that we have here.
Answer:

The prefix "Tetra" implies 4 Bromine atoms. The prefix "Deca" implies 10 fluorine atoms.
During a reaction, there are reactants and products. Reactants are the elements that are being added. Products are the result of the reactants.
2Na + Cl2 are the reactants.
2NaCl is the Product.
I hope this helps!