For the pin shown in Fig. 2.5, why is the third figure determined for the length of the pin uncertain? Considering that the third figure is uncertain, explain why the length of the pin is indicated as 2.85 cm rather than, for example, 2.83 or 2.87 cm.

Consider multiplying “26.2” by “16.43.” What would a mathematician say the answer is? What would a scientist say? Justify the scientist’s answer, not merely citing the rule, hut explaining it.

Two students were assigned to determine the mass of a sample of an unknown liquid. Student A used an ordinary laboratory balance that could determine mass to ±0.01 g. Student B used an analytical balance that could measure mass to ±0.1 mg. Each made four measurements, giving the following results: Student A: 8.19 g, 8.22 g, 8.21 g, 8.25 g Student B: 8.2210 g, 8.2210 g, 8.2209 g, 8.2210 g 2. Which student is more precise? A B