Making it through flight-attendant training is no picnic either, and flunking out results in not getting hired, Annette Long, a flight attendant with 13 years of experience, tells Business Insider.
Using a technique first devised by Karplus and Berger in 1970, a second part was added to the volume displacement task. The full task is done with three graduated cylinders with equal amounts of water and three marbles. The marbles have the following characteristics: The first marble is a large glass marble (18.5g). The second marble is a large steel marble, the same volume as the glass marble but more massive or heavier (66g). The third marble is a small steel marble, much smaller than the glass marble but the same mass or weight as the glass marble (18.5g). The protocol is as follows. The subjects are shown all three marbles and cylinders with water.
Best Answer: Basically, density is the amount of mass (molecules/matter) per an area unit. Imagine a box that's half-filled with 15 blue marbles. If that box could be divided into 5 parts and all the parts would have the same number of marbles, you'd get 3 marbles in each box part. That's the density; the number of marbles per box part. Now imagine that same whole box, and you add 5 white marbles. This would be the salt, which would make the water saline.