| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | | Demanding |
| ★★★★ | | Difficult |
| ★★★★★ | | Very difficult |
Determine the coefficient of linear thermal expansion of the metal tube. What metal the tube could be?
Answer: $22\cdot{10^{-6}}\frac{1}{℃}$
| Difficulty | Secondary School | High school/other |
| ★ | Basic | Easy |
| ★★ | Demanding | Basic |
| ★★★ | | Demanding |
| ★★★★ | | Difficult |
| ★★★★★ | | Very difficult |
Determine the coefficient of linear thermal expansion of the metal tube. What metal the tube could be?
Answer: $13\cdot{10^{-6}}\frac{1}{℃}$
