Answer:
2 . Geometry
Step-by-step explanation:
Egyptians were skilled in the study of geometry which they used for the development of their civilization. The great pyramids they built are the visible and still surviving evidence of their vast knowledge.
For the construction of the pyramids, they had to develop great geometrical precision and follow it so the structures would be precise and developed. Their basis is the square, and all of their sides are exactly the same. The archeological evidence found in Egypt shows that they know the properties and proportions of shaping the pyramids and making them so they would stand. This proves their usage of geometry.