What characteristics of the orbiting stars do we need to measure in order to calculate the mass of the central object, sgr a*?

Awatershed is a piece of land that drains water into a particular stream, lake, or river. which of the following factors often negatively impacts the water quality in a watershed? a.) wetlands b.) pollution c.) irrigation d.)rainfall

Where does the availability of water pose the greatest problem

Summary of the impact of the physical environment on settlement patterns and economic activities for ukraine