Answer: 21 minutes
Explanation: A complete revolution has 360°. The tower rotates completely after 60 minutes, which means:
360° - 60 min
The restaurant rotated 126° while the visitor was at the tower, so using proportionality rule:
360° - 60 min
126° - t min
![t=(126*60)/(360)](https://img.qammunity.org/2021/formulas/mathematics/high-school/6qpzcctugy9ubd0tgt8ccqkvf1edu3t9p9.png)
![t=(126)/(6)](https://img.qammunity.org/2021/formulas/mathematics/high-school/3tv8b32v8nv0xudyazowwddfnrb67u7qgh.png)
t = 21
The visitor was at the tower for 21 minutes.