A test carriage moves along a straight track. Its velocity is recorded at several times. The velocity changes uniformly between consecutive readings.
| Time (s) | Velocity (m/s) |
|---|---|
| 0 | +5.0 |
| 2.0 | +5.0 |
| 6.0 | -3.0 |
| 8.0 | -3.0 |
Calculate the total distance travelled and the displacement of the carriage during the 8.0 s.