Apiston–cylinder device initially contains 2 kg of refrigerant-134a at 800 kpa and 84°c. at this state, the piston is touching on a pair of stops at the top. the mass of the piston is such that a 500-kpa pressure is required to move it. a valve at the bottom of the cylinder is opened, and r-134a is withdrawn from the cylinder. after a while, the piston is observed to move and the valve is closed when half of the refrigerant is withdrawn from the cylinder and the temperature in the tank drops to 20°c. the properties of r-134a at various states are v1 = 0.033172 m3/kg, u1 = 294.504 kj/kg, h1 = 321.042 kj/kg, v2 = 0.042115 m3/kg, u2 = 242.42 kj/kg, and h2 = 263.48 kj/kg.

Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.

Marcella is a four-year-old girl who is a victim of emotional child abuse. based on the child and family services improvement and innovation act of 2011, which action should the government take for marcella? a. the state should arrest marcella’s abuser. b. the state should find a home for marcella as soon as possible. c. the state should enforce stricter laws in the area where marcella resides. d. the state should provide medical assistance to marcella.

Which radioisotope is used in dating geological formations?