In chapters 1 and 3, elizabeth kolbert visits scientists in the arctic and sees numerous examples of the effects of warming in the arctic. list three examples of natural (not human) changes due to warming in the arctic. in your example note where the change is taking place, what the change is, and how it is related to warming?

At steady state, air at 200 kpa, 325 k, and mass flow rate of 0.5 kg/s enters an insulated duct having differing inlet and exit cross-sectional areas. the inlet cross-sectional area is 6 cm2. at the duct exit, the pressure of the air is 100 kpa and the velocity is 250 m/s. neglecting potential energy effects and modeling air as an 1.008 kj/kg k, determine ideal gas with constant cp = (a) the velocity of the air at the inlet, in m/s. (b) the temperature of the air at the exit, in k. (c) the exit cross-sectional area, in cm2