What does muscular strength measure

Which statement about covalent bonds is true

The first law of thermodynamics states that heat added to a system is neither created nor destroyed but is transformed ⇒ as it changes into other forms of energy.

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error