Relative location isn't the exact location so they would have to be using their mental imagery of a map. For example, after you go to fro a place so many times, you will grow accustomed to it thus by using mental imagery of a map would be a good answer.
A wall stands using gravity. It is constantly being pulled down. Many also place them in ways that they dig into the ground, and almost make a socket just for the wall to be placed, using the land that is there. More and more walls are placed and eventually, they make flooring and a roof.
Hope that helped!
Over half of India's population works in agriculture, and monsoon rains directly affect their incomes and livelihood. Agriculture adds up to more than 15% of India's Gross Domestic Product (GDP), which means that when crops fail because of too little rain, the economy suffers.
Water Erosion
Wind Erosion
Glacier Erosion
Sea Erosion
Soil Erosion
