 Complete the following phrase:  After completing his degree in mathematics, Person joined the United States Department of Commerce as a physical science technician. In the late 1950s the Department of Commerce was responsible for monitoring earthquake activity. He used a seismograph that was set up in the lobby of the Herbert C. Hoover Building. Person was responsible for the maintece of the seismograph, and changed the rotating drums that recorded the seismic activity. Person first became involved with science communication in the lobby of the Commerce building, telling the curious people who crowded around the seismograph about earthquakes. He achieved his professional status in geophysics after the 