A plant hopes to cool a steam line by sending it through a throttling valve to expand it to atmospheric pressure. The steam enters the valve at 550C and 250 bar. The expansion in the valve happens so quickly that it can be assumed that any heat loss across the valve is negligible. a) Define the system. State whether it is open or closed, steady-state or not, adiabatic or not. (1 pt) b) Develop the reduced energy balance for this process by starting with the full (correct form) EB, reducing the terms, and justifying any terms that can be neglected. (2 pt)