申論題

4. Based on the Douglas sea scales, The following are parts of the tables of the state of the sea (The wind generated waves) and the state of swell (The background swell).

The following wave was what you observed at sea at noon time:
Wave length (L= 220 m) and Wave height (H=3 m)

Please answer the following questions:

(2)What is the swell degree of this wave? How to express it?