Frederick was the last Hohenzollern monarch titled King in Prussia.
Answer:

Explanation:
➤ When a few companies dominate the market, it’s called Oligopoly
An Oligopoly is referring to when a few companies dominate, overpower or become more successful or larger than other companies or markets. It does not matter how powerful the dominated or dominating companies are. Oligopoly is simply referring to a few companies. Although only a few firms dominate, it is possible that many small firms may also operate in the market.
- Mordancy
Here you go and hope this helps.
It will add another slave state to the nation