How can a vector be determined if its rectangular components are known?

Acube has a volume of 2011 cubic inches. what is the angle measure between a side of a cube and its interior diagonal?

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)

Awave that is traveling fast can be said to have a high a. frequency b. speed c. wavelength d. amplitude e. period f. none of these