What are the chief crops of the region

Where was oil production at its highest in the 1980s and still remains important to the russian economy? central asia the ural mountains russian siberia the caucasus region

After railroads, the next revolution of transportation came with the development of (a) automobile (b) telegraph (c) steam engine

Ascientist makes a map using gis. one layer is an aerial photograph of farmland. other layers show water level changes and how crop cover has changed over time. what might the scientist be studying?