A cube whose side length is 5 is shown below. Let P be on edge AB such that AP = 2, and let Q be on edge AE such that AQ = 1. The plane passing through points C, P, and Q intersects DH at R. Find the length DR.

A cube whose side length is 5 is shown below. Let P be on edge AB such that AP = 2, and let Q be on edge AE such that AQ = 1. The plane passing through points C, P, and Q intersects DH at R. Find the length DR.