List two reasons why the limestone blocks of the pyramids were so difficult to push across land.

Because they were so heavy, and the sand made it harder to pish them.

The limestone rocks of pyramids were very difficult to push across the land because of the following reasons-

The pyramids were comprised of two rocks, namely the inner rocks are limestone ad the outer rocks are granite. Granite is a very hard rock and contains quartz that are resistant to weathering. Each of this blocks were so heavy to push or move from one place to another.Due to the desert environment, the area is rich is sand and this played an important role by creating friction between the blocks of rock and the land surface. This is why the blocks were so difficult to move.

Alkaline earth metals are found in group 2 of the periodic table.