Answer :
Assuming it's a perfect gas, we have PV=nRT hence V and T are proportional. T increased by 2600/650=4 times hence the volume will be 4 times bigger, which is 200L
Charles' Law: V1 = V2 V2 = V1T2 V2 = (50L)(2600K) = 200L
T1 T2 T1 (650K)
T1 T2 T1 (650K)