night815·3 वर्ष पहले·discussInstead of building underground you could use earthen materials but stay above ground.https://www.youtube.com/watch?v=IuQB3x4ZNeA
night815·3 वर्ष पहले·discussExactly, isn't the point of research to publish your findings which explains the WHY?
https://www.youtube.com/watch?v=IuQB3x4ZNeA