The style declarations which apply to the text below are:

IMG.one {display: inline;}
IMG.two {display: block;}
IMG.three {display: block;
           margin-right: auto; margin-left: auto; width: auto;}
IMG.four {display: block;
          margin-right: auto; margin-left: auto; width: 50%;}
IMG.five {display: block;
          margin-right: 0; margin-left: auto; width: 50%;}

The image at the beginning of this sentence should be a 15px square.

The above image should be a 15px square with the same left edge as this text.

The above image should be a 15px square aligned at the center.

The above image should be a square resized so its width is 50% of the its parent element, and centered horizontally within the parent element: the document body in the first half, and the table in the second.

The above image should be a square resized so its width is 50% of its parent element, and aligned at the right edge of the parent element: the document body in the first half, and the table in the second.

TABLE Testing Section

The image at the beginning of this sentence should be a 15px square. The above image should be a 15px square with the same left edge as this text. The above image should be a 15px square aligned at the center. The above image should be a square resized so its width is 50% of the its parent element, and centered horizontally within the parent element: the document body in the first half, and the table in the second. The above image should be a square resized so its width is 50% of its parent element, and aligned at the right edge of the parent element: the document body in the first half, and the table in the second.