2) the xochicalco solar zenith tube xochicalco is an ancient city in central mexico at latitude 19 degrees n, and was populated by 20,000 or more people in the years 700-900 ad. a vertical shaft in the ground lead to an underground chamber, and on certain dates the sun shines directly down the "zenith tube." on how many days each year will this happen? what is the declination of the sun on these days? (5pts) a) on what days or the sun shine directly down the tube? (5pts) use either method listed below to you. b)