Look at the two units of measure below.
Which of them would you use to measure the top surface of your desk? Explain your thinking.
Since the surface of the top of a desk is flat and not just a straight line, it is a multi-dimensional quantity.
Surface is best measured by square units for surface area.
What part(s) of your desk could you measure using the linear unit? Draw a picture and show how that unit could be used.
There are many possible answers. Think about what parts of the desk could be measured with a ruler for possible linear measurements of dimensional values.