<span>The correct answer for 1 is perform military services. Vassals would have to fight wars for you and help you when it came to defending from others. The answer for 2 is It strengthened the idea that a monarch's power was limited, not absolute. They did it by giving more freedoms to the nobles who could now avoid being prosecuted if they disobeyed the king. The correct answer for 3 is Holy Roman Empire. Frederick I Barbarossa was the first Holy Roman Empire. It wasn't the entire Italy but rather the northern parts of it.</span>
Ideology of conservatism.
I hope this helps!
The answer is A. Drove production costs up. It drove production costs down, because they were able to take less time to make the products as well as less materials because 1) standardized parts were invented around the same time, and 2) they didn't have people preparing everything so materials weren't wasted.