Most street lights are made from one of two elements—mercury or sodium. explain why astronomers prefer that cities use sodium street lights instead of mercury street lights.

Astronomers prefer that cities use sodium street lights because the emission spectrum of sodium produces fewer lines than the emission spectrum of mercury -ally

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.