$3\mathrm{.}25.$ A scheme for finding the internal volume $V_B^t$ of a gas cylinder consists of the following

steps. The cylinder is filled with a gas to a low pressure $P_1,$ and connected through a

small line and valve to an evacuated reference tank of known volume $V_A^t.$ The valve is

opened, and gas flows through the line into the reference tank. After the system returns

to its initial temperature, a sensitive pressure transducer provides a value for the pressure

change AP in the cylinder. Determine the cylinder volume $V_B^t$ from the following data:

$V_A^t=256c{m}^3.$

$\frac{P}{P_1}=-0\mathrm{.}0639.$