Trebuchets are counterweight medieval siege weapons. The Byzantine empire was the first to use it ever. They were invented in Ancient China. Ancient Chinese invented it. Trebuchets were used to destroy castle walls or defenses. You would put a weight on a short part or a long piece of plywood. Then you make a sling and put a rock or whatever projectile you want to put in it.
Someone named Abu Musa Jabir ibn Hayyan made the first distilled spirit. He made it in the 13th Century. That’s a long time ago! It was made in India. People used it to make alcoholic beverages.
The man that invented the vertical windmill was called Heron of Alexandria. I would guess that it was made in Alexandria. It was made in 50AD. Once you set up a wind mill make sure the blades are a little bit tilted so it can catch air and spin. Windmills give electricity so you can power lights and fans ant thousands of other things.
The Chinese invented the stern-mounted rudder and thousands of people started using it. The triangle sail was also invented with it pretty much and people used both on one boat. It was invented in the 1st century in china. If the stern-mounted rudder turned the whole boat moves in that direction.