A thermistor has a response to temperature represented by R = Roe-0.1T where Ro = 10,000 Ώ, R = resistance, and T = temperature in degrees Celsius. Find the linear model for the thermistor operating at T = 20°C and for a small range of variation of temperature. ∆R = -135 ∆T

An air compression refrigeration system is to have an air pressure of 100 psia in the brine tank and an allowable air temperature increase of 60°f for standard vapor compression cycle temperatures of 77 f entering the expansion cylinder and 14 f entering the compression cylinder, calculate the coefficient of performance a. 2.5 b 3.3 c. 4.0 d. 5.0