| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | Demanding | |
| ★★★★ | Difficult | |
| ★★★★★ | Very difficult |
Illustrate distance effect on the intensity of radiation with graphical graph. Interpret the graph you draw.
Answer: The Geiger counter shows that the intensity of the radiation decreases rapidly as the distance increases.