The force required to compress the gas in a gas spring a distance x is given bywhere the c...

The force required to compress the gas in a gas spring a distance x is given by

where the constant is determined by the geometry of this device and k is determined by the gas used in the device. One such device has a constant of 200 lbf•in^1.4 and k = 1.4. Determine the work, in Btu, required to compress this device from 2 in to 7 in.