A student investigates the viscosity of a fluid by dropping a glass sphere into a tall vertical cylinder filled with glycerol to a depth of 1.20 m1.20\text{ m}1.20 m. Her classmate measures the time taken for the sphere to fall from the surface of the glycerol to the bottom of the cylinder.
Suggest the equipment used to measure:
They record their results in the table below:
| Run | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| Time taken (s) | 2.45 | 2.30 | 2.55 | 2.30 | 2.40 |
Use the data in the table to calculate the mean, median, and mode of their results.
The results are not very precise. Explain how you can tell from the data in the table.
Suggest a possible source of error in this experimental setup and how it could be improved.