An aerial survey drone completes a journey in three stages.
| Stage | Distance travelled | Time taken |
|---|---|---|
| Flies along a pipeline | 1.2 km | 80 s |
| Remains stationary while recording data | 0 m | 25 s |
| Flies to its landing point | 450 m | 30 s |
Calculate the average speed of the drone for the complete journey.