Answer : 3. "P1V1 = P2V2"
Explanation :

Answer: C) P1V1 = P2V2 Explanation: Ideal Gas Law :: The Combined gas law or General Gas Equation is obtained by combining Boyle's Law, Charles' Law, and Gay-Lussac's Law. It shows the relationship between the pressure, volume, and temperature for a fixed mass (quantity) of gas: P1V1T1 = P2V2T2   Hence, the Boyle's law P1V1 = P2T2, relates to ideal gas equation.