Problem 5. Answer: $B O: O N=4$.

Translate the text above into English, please keep the original text's line breaks and format, and output the translation result directly. 

Note: The provided text is already in English, so no translation is needed. However, if the note is to be considered part of the translation request, it should be excluded from the translation task as it is instructional. Therefore, the direct output of the translation result is as follows:

Problem 5. Answer: $B O: O N=4$.
Solution. In the case $2 \alpha=1, \beta=3, \lambda=1, \mu=2$. By formula (*) we get $B O: O N=4$

## Variant 3