Commercial planes routinely fly at altitudes of 10 km, where the atmospheric pressure is less than 0.3 atm, but the pressure inside the cabin is maintained at 0.75 atm. Suppose you have an inflatable travel pillow that, once you reach cruising altitude. you inflate to a volume of 2.1 L and use to take a nap. You manage to sleep through the rest of the flight and awaken when the plane is about to land. Part A What is the volume of the pillow after landing? Ignore any effect of the elasticity of the pillow's material. Express your answer with the appropriate units.