You place your pencil on your desk it stays there

What type of electromagnetic wave is used in security pens? a. x-rays c. microwaves b. visible light d. ultraviolet radiation select the best answer from the choices provided

When a 5.0kg cart undergoes a 2.2m/s increase in speed, what is the impulse of the cart

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.