The lowest possible temperature is absolute zero. However scientists have not reached this temperature, rather they have come very close to absolute zero.
Precipitation from the sky to the earth can come in several forms. Four types are:
1) Rain
2) Snow
3) Sleet (think of a more liquidity slushy snow)
4) Hail (pretty much solid chunks of ice)
Line spectra are obtained when individual elements are heated using a high-voltage electrical discharge. This heating causes excitation of the element and a subsequent emission of distinct lines of colored light are obtained. Each element has its own unique emission line spectrum; therefore, if any of the tested substances were the same, their spectra would match. However, this is not the case so none of the substances are the same.
hope it helps!
