Which of the following represents the most matter?

3.5 kg

350 g

3.5 x 10³ hg

3.5 x 10⁴ cg

In order to assess these masses, one must convert all the masses to a single a unit so that they can easily be compared ...

3.5 kg = 3.5 kg

350 g = 0.35 kg

3.5 * 10³ hg = 3500 hg = 350 kg

3.5 x 10⁴ cg = 35000 cg = 0.35 kg

∴ 3.5 * 10³ hg is the largest mass.