The base of a solid right pyramid is a square with an edge length of n units. the height of the pyramid is n − 1 units. a solid right pyramid has a square base with an edge length of n units. the height of the pyramid is n minus 1 units. which expression represents the volume of the pyramid? one-thirdn(n − 1) units3 one-thirdn(n − 1)2 units3 one-thirdn2(n − 1) units3 one-thirdn3(n − 1) units3