Whats three enlightened monarchs during the eighteenth century were?

They were:

The Empress born in Prussia in 1729, more precisely in the city of Stettin, was the great modernizer of the Russian Empire despite being a foreigner. In 34 years she has governed with absolute obstinacy, extending the frontiers of the Empire, promoting the arts and enacting laws to improve education, as well as carrying out a real reform in the administration.

Frederick II was king of Prussia, a kingdom that existed from 1740 to 1786 where it is today Germany. A great military leader, he turned Prussia into a great European power. His military genius, his love for the arts and his modern administration earned him the title Frederick the Great.

Joseph II was Emperor Romano-Germanic and Archduke of Austria from 1765 until his death, besides King of Hungary, Croatia and Bohemia from 1780.

the answer is jerusalem

well that depends on how deep the hole is. you'd first go through te crust of the earth, then the upper mantle, then the lower mantle then the outer core, then the inner cor then you'd be stuck in the core to melt.