Part A - Minimum thickness for a cylinder A cylindrical tank is required to contain a gage pressure 700 kPa . The tank is to be made of A516 grade 60 steel with a maximum allowable normal stress of 150 MPa . If the inner diameter of the tank is 3 m , what is the minimum thickness, t, of the wall? Express your answer with appropriate units to three significant figures.

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false

The drive force for diffusion is 7 fick's first law can be used to solve the non-steady state diffusion. a)-true b)-false

To save energy, the air supply to a 2000 ft office has been shut off overnight and the room temperature has dropped to 40°f. in the morning, the thermostat is reset to 70°f and warm air at 120 f begins to flov in at 200ft'/min. the air is well mixed within the room, and an equal mass flow of air at room temperature (changing with time) is withdrawn through a return duct. the air pressure is nearly 1 atm everywhere. ignoring heat transfer with the surroundings and kinetic and potential energy effects, estimate how long it takes for the room temperature to reach 70°f. plot the room temperature as a function of time.