How to read measurements on a drawing with a 2:1 scale, showing cm, mm, and 0.1mm increments?

Let's break down where each unit is on your drawing:

1. Centimeters (cm): These would be the major divisions along the main horizontal line that extends to the right from the '0' mark. In your drawing, this is the long horizontal line. You would mark 1 cm, 2 cm, 3 cm, etc., along this line (each actual centimeter representing 2 cm on your drawing because it's a 2:1 scale).

2. Millimeters (mm): These are the subdivisions of the first centimeter, located to the left of the '0' mark on your main horizontal line. In your drawing, this is the bottom edge of the grid section on the left. Each small segment along that bottom line represents 1 mm.

3. Tenths (0.1 mm): These are represented by the vertical divisions on the far left side of your grid. You've drawn a vertical line and divided it into 10 parts. The horizontal lines extending from these vertical divisions, combined with the diagonal lines, allow you to read the "tents" or 0.1 mm increments.

So, you read the main centimeters from the right, the millimeters from the bottom-left, and the tenths by moving up the vertical lines and across the diagonal lines in the left grid section.