What is the true answer in this question cramming for a test or project it is no or yes,

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=

Which wave is the result of amplification and produces a louder sound

The molecular weight of oxygen gas (o2) is 32 while that of hydrogen gas (h2) is 2. prove that under same physical conditions, the velocity of sound in hydrogen is four times that in oxygen