Answer : The volume of gas will be, 113.5 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 = 60 atm
= final pressure of gas = 30 atm
= initial volume of gas = 29 L
= final volume of gas = ?
= initial temperature of gas = 115 K
= final temperature of gas = 225 K
Now put all the given values in the above equation, we get:


Therefore, the volume of gas will be, 113.5 L