A student investigated the reaction of copper powder with oxygen in the air. Three samples of copper powder, AAA, BBB, and CCC, were heated in open crucibles until they were completely oxidised. The table below shows the mass measurements obtained:
| Sample | Mass of sample before heating in g\text{g}g | Mass of sample after heating in g\text{g}g | Increase in mass of sample in g\text{g}g |
|---|---|---|---|
| AAA | 3.42 | 4.14 | 0.72 |
| BBB | 3.35 | 4.13 | ZZZ |
| CCC | 3.50 | 4.40 | 0.90 |
Calculate the value of Z Z\,Z in the table.
Calculate the mean increase in mass of the three copper samples, AAA, BBB, and CCC.