<u>Answer:</u> The density of the quartz is 2.68 g/mL
<u>Explanation:</u>
We are given:
Volume of graduated cylinder = 50.3 mL
Volume of quartz + graduated cylinder = 64.8 mL
Volume of quartz = [64.8 - 50.3] mL = 14.5 mL
To calculate the density of substance, we use the equation:

Mass of quartz = 38.9 g
Volume of quartz = 14.5 mL
Putting values in above equation, we get:

Hence, the density of the quartz is 2.68 g/mL
<span>The Answer </span>should be<span> .074 M</span>
If an electron moves up from the first orbit to the higher energy levels, energy will be absorbed by the electron itself and no emission line produced.
But if it moves from the orbits 6,5,4 and 3 to orbit 2, energy will be released by the electron and different emission lines wll be produced.