10.4. A 10.0-ft 3 compressed-air tank is being filled. Before the filling begins, the tank is open t the atmosphere. The reading on a Bourdon gauge mounted on the tank increases linearly from an initial value of 0.0 to 100 psi after 15 seconds. The temperature is constant at 72F, and atmospheric pressure is 1 atm. a. Calculate the rate n(lb mole/s ) at which air is being added to the tank, assuming idealgas behavior. (Suggestion: Start by calculating how much is in the tank at t=0.) b. Let N(t) equal the number of lb-moles of air in the tank at any time. Write a differential balance on the air in the tank in terms of N and provide an initial condition. c. Integrate the balance to obtain an expression for N(t). Check your solution two ways. d. Estimate the lb-moles of oxygen in the tank after two minutes. List reasons your answer might be inaccurate, assuming there are no mistakes in your calculation