Tank Object and Sequence

In this illustration, a tank rolls over a hill.  Note that its scope changes position over the course of the animation.  First, identify the parts of the object that change over the course of the sequence.  Just the top, right?  The bottom just moves linear, the top part rotates.  In the upper four frames of the illustration, we see what the thank looks like in its completion over the course of this short bit of time.  Note how the second row of animations display that the bottom of the tank rotates as well.  Below that, we see what the tank appears like as its upper part pivots 180˚.  This part illustrates how to make a thin cylinder turn from sideways to facing, in just a few frames.

note:  The tank later became known as the "Paco Bell Cannon" when it was announced that one of the rules of drawing flipbooks via the Analog Basic illustration method involves never demonstrating anything actually destructive.  Paco Bell Cannon plays one song constantly and serves Mexican food.