Are there any other methods you could use to determine phosphate content in the colas

Concentration of phosphate (phosphoric acid mostly) in soft drinks can be measured with acid-base titration. For titration sodium hydroxide solution is used. Hydrogen ions (H⁺) from the first dissociation of phosphoric acid react with hydroxide ions from sodium hydroxide: 
H₃PO₄(aq) + OH⁻ (aq) → H₂O(l) + H₂PO₄⁻ (aq).
Use pH sensor to monitor pH of titration solution. Determine the equivalence point (the region of most rapid pH change), measure the volume of sodium hydroxide titrant used at the equivalence point and calculate concentration of phosphate with concentration of used titrant.

4- c, because all matter stays the same no matter what. it is still there. 5- b, because matter is known as mass. 6-c because, flammability is a chemical property. malleability is changing the shape of an object.