A crate is sliding on the floor. If there is a total force acting on the crate in the same direction as it is sliding, the crate would A) slow down
B) speed up
C) remains the same speed
​​​​​​​ D) slow down, change direction and then speed up going the other way,
E) remains the same speed but changes direction

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)