Simplex volumes in hyperplane arrangements

We study the dual variants of the Erdős’s distinct distances and unit distance problems. Instead of considering distances determined by points, we consider simplex volumes determined by hyperplanes. We investigate: (1) the maximum number of unit $d$-volume $d$-simplices determined by an arrangement of $n$ hyperplanes in ${\mathbb{R}}^d$, (2) the maximum number of minimum/maximum $d$-volume $d$-simplices determined by an arrangement of $n$ hyperplanes in ${\mathbb{R}}^d$, and (3) the maximum number $D_d(n)$ such that any arrangement of $n$ hyperplanes in ${\mathbb{R}}^d$ in general position contains $D_d(n)$ hyperplanes forming $d$-simplices of distinct $d$-volumes.