Acolumn of soldiers, marching at 121 steps per minute, keep in step with the beat of a drummer at the head of the column. it is observed that the soldiers in the rear end of the column are striding forward with the left foot when the drummer is advancing with the right. what is the approximate length of the column? (take the speed of sound to be 343 m/s.)

There’s a first “clump”/drum beat every half second. That clump will travel about 170m in half a second. Someone 170m away would do their “clump” as the second “clump” was taking place. I think.

-4 on

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.