a safe chemical with(the lowest boiling point 6f)any gas, which fhakes helium good for
cooling medical equipment o extremely 16w temperatures. Helium is also used(in
combinations of breathing gases for deep-sea diving replacing nitrogen gas, which can
hake people'sick at high pressures.
Helium is collected as a by-product of the oil and gas industry. In the 1920s, the US
government began to store helium at the National Helium Center (NHC), to_use in
military flying machines. By the 1960s, the US military had new uses for helium, such as
cleaning fuel tanks for rockets. By the 1990s, the NHC was in enormous debt from
storing helium, so a law was passed in 1996 forcing the NHC to sell all of its helium by
等、
2A15 no matter the market price
