Use the diagram in the box to convert the given measurement to the unit indicated. \[ 0.021 \mathrm{~mm} \text { to } \mathrm{m} \] $\mathrm{m}$ (Type an integer or a decimal.)

Step 1 ：The question is asking to convert a measurement from millimeters (mm) to meters (m). The conversion factor between these two units is that 1 meter is equal to 1000 millimeters. Therefore, to convert from millimeters to meters, we need to divide the number of millimeters by 1000.

Step 2 ：Given that the measurement in millimeters is 0.021, we divide this by 1000 to get the measurement in meters.

Step 3 ：\(\frac{0.021}{1000} = 2.1 \times 10^{-5}\)

Step 4 ：The final answer is \(\boxed{2.1 \times 10^{-5}}\) meters, or in decimal form, \(\boxed{0.000021}\) meters.