An investigator measured the change in mass of courgette (zucchini) cylinders immersed in a 0.8 mol/dm³ sodium chloride solution for 45 minutes. The results of this experiment are recorded in the table below:
| Courgette cylinder | Mass at start in grams | Mass after 45 minutes in grams | Change in mass in grams |
|---|---|---|---|
| 1 | 4.8 | 4.1 | -0.7 |
| 2 | 4.7 | 4.2 | -0.5 |
| 3 | 4.9 | 4.3 | -0.6 |
Give two ways that this method could be improved to obtain more accurate results.
