Julia can swim at 3.5 km/h in still water. she attempts to head straight northacross a river with a current flowing at 1.2 km/h west. what is her resultantvelocity?   in this problem , at what angle should julia aim in order to land directly across the river from her start point?

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)