A pipeline containing air at 9.5 bar (abs) and 15oC develops a small leak to atmosphere, where the atmospheric pressure is 1.02 bar (abs). If the hole may be considered to have a diameter of 0.5 mm, calculate the initial mass flow rate of the escaping air if the discharge coefficient of the hole is assumed to be 0.6 and the flow is assumed to be (a) isothermal; or (b) adiabatic. The adiabatic expansion constant (k) should be assumed to be 1.4, and the molecular weight of air is 29 g mol-1. (Answers: (a) 0.24 g s-1; (b) 0.27 g s-1)