How do you measure r1 r2?

To measure r1 and r2, you typically use a measurement tool such as a caliper or a ruler, depending on the context. For geometric shapes, r1 and r2 often represent the radii of circles or spheres, which can be measured directly from the center to the edge. In electrical contexts, r1 and r2 may refer to resistances in a circuit, which can be measured using a multimeter. Always ensure measurements are taken at consistent reference points for accuracy.