At an altitude of 40 km above the earths surface, the atmospheric pressure is 5.00 torr, and

Question:

At an altitude of 40 km above the earth’s surface, the atmospheric pressure is 5.00 torr, and the surrounding temperature is −20(C. If a weather balloon is filled with 1.000 mol of Heat 760 torr and 22(C, what is its
a. Initial volume before ascent?
b. Final volume when it reaches 40 km in altitude? (Assume the pressure of the gas equals the surrounding pressure.)