0.09 is one tick mark Behind the 1/10 or 1 over 10 mark.
0.9 is the exact mark labled 9 over 10 or 9/10.
0.19 is exactly the mark behind the 2/10 mark or 2 over 10.
0.190 is on exactly the same mark as the one above-- on the mark behind the 2/10 mark.
0.019 is does not have a place on the strip. It is in the thousandths place not the hundredths or tenths places. That is why it doesn't have a place on the strip
Hope this helps you! :)