(economics involves business and financial activities that show how people choose to use their limited resources (land, labor, and capital goods) to produce, exchange, and to consume goods and services)

(the science of water which denotes the study of the properties, distribution, and movements of water on land surfaces, in the soil, and through the subsurface rocks of the earth)

(There are estimated to be 10,000 million insects living in each square kilometer of habitable land on earth or 26,000 million per square mile)