What does waining mean?

Africtionless piston-cylinder contains 50 l of saturated liquid r-134a. the piston has a mass and an area resulting in an applied pressure of 500 kpa on the refrigerant. the refrigerant is now heated until its temperature rises to 70∘c. calculate the work (in kj) done during this process.

Name the non metal condut electricity

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value