The correct answer to this open question is the following.
The Great Ancient Egypt civilization had many qualities. One of them was that they were great traders. Egyptian Pharaohs knew this and made trade a priority in Egypt.
Egypt traded with other nations goods such as gold, grain. linen, and papyrus. They used the barter system and imported ivory, copper, ebony, and cooper. They were good sailors and used the Nile River to transport the goods. With the wealth they obtained from trade, Egyptian were capable of building one of the greatest pyramids edifications known by humans. For instance, the Giza complex, next to Cairo, where the Great Pyramid is located. There were other pyramids edification in places such as Memphis, about 60 miles from Giza.
The other great construction they could build with that richness was the Pharaoh's palaces in different parts of Egypt. The best examples are the Temple of Luxor and the Temple of Karnak, next to the Nile River.