Answer:
4 L or 4000 mL
Explanation:
This question asks for the use of combined gas law:
(P1)(V1) / (T1) = (P2)(V2) / (T2)
...where pressure (P) is in atm, volume (V) is in liters, and temperature (T) is in kelvin.
1000 ml is 1 L, and everything else is already in the right units.
(1 atm)(1 L) / (20 K) = (0.5 atm)(V2) / (40 K)
Just solve the equation for V2, and you get a new volume of 4 liters
(1)(1) / (20) = (.5x) / (40)
1 / 20 = .5x / 40
2 = .5x
x = 4
