Answer:
Glass is the most common material used to construct lens elements, due to its good optical properties and resistance to scratching. Other materials are also used, such as quartz glass, fluorite, plastics like acrylic (Plexiglass), and even germanium and meteoritic glass.
Answer:
Excavation of sites and research of artifacts and other physical remains to learn about human history and prehistory.
Explanation:
the legislative council exists only in six states.
