The water particles move perpendicular to the source of the sound wave. The water particles move in the same direction as the vibrating source of the sound wave. The water particles move in random patterns because the sound is diffracted in many directions
No force is required to lift that balloon. In fact, force is required to hold it down, and if you let go, it's up, up, and away.
Since the balloon's density is less than the density of the air around it, it's lighter than the air it displaces, there is a net upward buoyant force acting on it, and it floats up !
Well you first need an equation, then put it on a graph
1) The area of a circle is given by

where r is the radius of the circle. In this problem, we are told that the area is

so we can rearrange the previous equation to calculate the radius:

And now we can find the circumference, by using the formula:

Therefore, the correct answer is D. 75.3984 meters.
2) The volume of a cube is given by:

where L is the length of the edge. In this problem, L=6 cm, therefore the volume of the cube is

and so, the correct answer is A. 216 cu. cm.