Why were pyramids often started but never completed?

Pyramids were started but never completed because they took hard work to make, and each block was very heavy. Hope it helps.

the main inference that can be drawn from jean jacques rousseau's book the social contract is: a. people can enjoy civil and physical freedom, even if it sometimes harms society.

the process is called revolution because it was a process of great economic-social transformations that began in england in the xviii century.

the industrial mode of production spread throughout much of the northern hemisphere throughout the xix and early xx centuries.

the effect of this revolution was the distance between the countries, with respect to economic and political power.   after all, not all industrialized at the same time, remaining in the condition of suppliers of raw materials and agricultural products to the industrialized countries.

these differences mark to this day the nations of the world that are divided between developed and developing countries. one way to measure whether a country is advanced is to assess how industrialized it is.