What is freud's term for the primitive, biological side of personality?

Which changes of state do the labels represent? a: b: c:

The vapour pressure of benzene is 53.3 kpa at 60.6 °c, but it fell to 51.5 kpa when 19.0 g of a non-volatile organic compound was dissolved in 500 g of benzene. calculate the molar mass of the compound.

What does si stand for,when referring to a system of measurement