Question: What is the name of this town in Rensselaer County, New York, which is emcompassed by Rensselaer Plateau with a population of 2,130?
Sentence (from "Rensselaer Plateau"): The Rensselaer Plateau is a small plateau located in the central portion of Rensselaer County, New York; it generally encompasses significant parts of the towns of Berlin, Stephentown, Sand Lake, Poestenkill, and Grafton, along with small sections of several other nearby towns.
Relevant evidence: Yes