The steepest slope would be South. It is the area where the drop is straight down and there is the least flatland on each cliff. The drop from 20 to 70 is the steepest drop on the south side.
2) The difference in the elevation between the second and fourth layer on the map would be (-20) Each layer interval is (-10) so two layers down would be -20. 3) The best place to build a home would be the flattest area on the map with the most area which would be letter B, South-West.