When you walk into a dark room and turn the light on, do the electrons travel all the way from the switch to the light?

The denser a substance, the more tightly packed it is. the table below shows the volume and mass of two different substances. comparison of substances substance volume (cm3) mass (g) r 22 10 s 55 25 which of the two substances is more tightly packed? object r is more tightly packed. object s is more tightly packed. both objects are packed equally tightly. this cannot be determined.