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How do I calculate the minimum deflection I can sense with a strain gauge, like the BF350-3AA?

I have a strain gauge (the BF350-3AA), and I will be connecting it to an HX711-based amplifier sensor.

From its low-quality datasheet, I've pulled out the following figures:

  1. Nominal Resistance: 350 ohms
  2. Sensitivity Coefficient (which I believe is also called the Gauge Coefficient): 2.1
  3. Sensitivity Coefficient Dispersion: <+/- 1%
  4. Transverse Effect Coefficient: 0.4%
  5. Strain Limit: 2%

Ultimately, the quantity that I want to measure is the number of micrometers of deflection over the lenghth of the gauge. What is the minimum sensitivity (or precision) of deflection I can measure?

Bonus question: What formula do I use to calculate the deflection as a function of resistance (or resistance change)?