What is the level of a handwritten binary tree?

Normal level.

This is normal for calligraphy grades.

Calligraphy is a form of artistic expression that shows the beauty of words. In a broad sense, calligraphy refers to the writing rules of text symbols. Calligraphy can be divided into Chinese calligraphy, Mongolian calligraphy, Arabic calligraphy, etc. Among them, Chinese calligraphy is a traditional art unique to Chinese characters. It is known as wordless poetry, invisible dance, pictureless painting, etc. It can be used for calligraphy. Type design, stone inscriptions, pattern design and many other aspects.