Which is a unique feature of venus? a. its surface is well below freezing. b. its surface is hot enough to melt lead. c. it has liquid water on the surface. d. it is heavily cratered.

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground.what is his gravitational potential energy above the ground?

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?

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)