Mahalanobis was an Indian scientist and applied statistician. He is best remembered for the Mahalanobis distance, a statistical measure he used in his pioneering studies in anthropometry—the study of human body measurement for use in anthropological classification and comparison. He founded the Indian Statistical Institute and contributed to the design of large scale sample surveys. His survey methods have been used to study things like tea-drinking habits, crop acreage, and what else? Discuss