three emission line involving three energy levels in an atom occur at wavelength x,1.5 x, and 3.0x nm which wavelength corresponds to the transition from the highest to the lowest of the three energy levels​

Can someone me with these questions plz.

A50.0 ml sample of gas at 20.0 atm of pressure is compressed to 40.0 atm of pressure at constant temperature. what is the new volume? 0.0100 ml 0.325 ml 25.0 ml 100. ml

What are the advantages of using the metric system? designed as a decimal system making conversions simpler more accurate system of measurement has prefixes that correspond to an amount to use with all base units used by the entire scientific community