Answer: Thus the volume of the balloon at this altitude is 419 L
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,

where,
= initial pressure of gas = 751 mm Hg
= final pressure of gas = 495 mm Hg
= initial volume of gas = 340 L
= final volume of gas = ?
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:


Thus the volume of the balloon at this altitude is 419 L
<span>1. The balanced equation for the reaction between magnesium sulfate and ammonia is MgSO4 + 2NH4OH → (NH4)2SO4 + Mg(OH)2
2. The reaction between magnesium sulfate and ammonia is double displacement.</span>
I think it’s B but not 100% sure