Problem set 2 questions 3c, 3e

For 3c, the volume of water, would it just be equal to mass? since 1g=1cm3 for water For 3e, how can I know the volumetric water content at saturation?

For 3c you need to take in consideration density of water to recalculate mass of water into volume of water.

As for your 2nd question, here is a hint - at saturation all soil pores are filled with water.

How do we find the pore volume?

From info provided in the question and typical value for particle density for mineral soils