The mean number of words per minute (WPM) typed by a speed typist is 73 with a variance of 144. What is the probability that the sample mean would differ from the population mean by greater than 0.6 WPM if 77 speed typists are randomly selected? Round your answer to four decimal places.

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)

An electron in an x-ray machine is accelerated through a potential difference of 1.00 × 104 v before it hits the target. what is the kinetic energy of the electron in electron volts?

Explain how a step-down transformer makes electricity safe for use in homes