What is aviation? What is the difference between aviation and flight?

Aviation refers to flying using an aircraft, like an aeroplane. It also includes the activities and industries related to flight, such as air traffic control. The biggest of the many uses of aviation are in air travel and military aircraft . The main difference between aeronautics and aviation is their focus. Aeronautics involves the study of the science, design, and manufacture of flying vehicles while aviation involves flying or operating an aircraft and various activities surrounding mechanical flight and the aircraft industry

In general, the greater the degree of undercooling of a liquid melt, the smaller the critical radius of the nuclei formed.

you forgot the rest of the question sorry