Question

you can check the thickness of the flooring the subfloor material and its thickness by referring to building plans; lifting out a supply air register; asking the owner; measuring the overall floor thickness and subtracting the joists; drilling a small pilot hole in an inconspicuous spot. question 34 handrails on open stairs should typically be 20 to 24 inches high; 22 to 26 inches high; 30 to 36 inches high; 34 to 38 inches high; 38 to 42 inches high

Explanation:

Answer:

First question: drilling a small pilot hole in an inconspicuous spot
Second question: 34 to 38 inches high