yes
A cube has six sides; a pyramid has five, if you count the bottom of the base.
7
rectangular prism pyramid
square based pyramid
It depended on the size of the pyramid. The Great Pyramid at Giza is comfortably over two million, with some estimates going up to 3.5 million or greater. Smaller pyramids would take fewer stones, as would pyramids which substituted different building materials.
There are fewer organisms at the top of a biomass pyramid because energy is lost as it is transferred from one trophic level to the next. This means that less energy is available to support the growth and maintenance of organisms at higher trophic levels, resulting in fewer individuals.
A rectangular prism has 6 faces. A pentagon prism has 7 faces. Therefore a rectangular prism has one less face than a pentagonal prism.
Any polyhedron other than a pyramid.
A square pyramid has 5 vertices. A triangular prism has 6 vertices. The pyramid has -1 more vertex than the prism, or 1 fewer.
It looks like a triangle. Lots of young people at the bottom of the triangle, with fewer and fewer people as you go up the age scale.
A shape that has fewer than 8 faces and fewer than 10 edges is a triangular prism. A triangular prism has 5 faces (2 triangular faces and 3 rectangular faces) and 9 edges. It meets the criteria of having fewer than 8 faces and fewer than 10 edges.
A tetrahedron (triangular pyramid).