A measurement was taken three times. The correct measurement was 68.1 mL. Circle whether the set of measurements is accurate, precise, both, or neither.

a) 78.1 mL, 43.9 mL, 2 mL
- accurate
- precise
- both
- neither

b) 68.1 mL, 68.2 mL, 68.0 mL
- accurate
- precise
- both
- neither

c) 98.0 mL, 98.2 mL, 97.9 mL
- accurate
- precise
- both
- neither

d) 72.0 mL, 60.3 mL, 68.1 mL
- accurate
- precise
- both
- neither

To determine whether sets of measurements are accurate, precise, both, or neither, one must consider how close the measurements are to the correct value and to each other. Only set (b) is both accurate and precise, while set (a) and (d) are neither, and set (c) is only precise.

In the context of measurements, accuracy refers to how close a measurement is to the correct value, while precision refers to how close a series of measurements are to each other, regardless of whether they are close to the correct value or not. Using these definitions, let's evaluate each set of measurements:

(a) 78.1 mL, 43.9 mL, 2 mL: This set is neither accurate nor precise because the measurements are far from both the correct value and each other.

(b) 68.1 ml, 68.2 mL, 68.0 mL: This set is both accurate and precise as the measurements are very close to the correct value (68.1 mL) and to each other.

(c) 98.0 mL, 98.2 mL, 97.9 mL: This set is precise because the measurements are close to each other, but it is not accurate since they're significantly different from the correct value.

(d) 72.0 mL, 60.3 mL, 68.1 mL: Although one measurement is correct, the set is neither accurate nor precise overall because the measurements are not consistently near the correct value or each other.

Therefore, based on the provided measurements and the correct measurement of 68.1 mL, the answers to the question are:

(a) Neither

(b) Both

(c) Precise

(d) Neither