Suppose the true value of a measurement is 276.6 cm. Which of the following represents the most positively biased, and imprecise group of measurements? a. Out of 10 observations, 9 are 278 cm, and one is 279 cm.
b. Out of 20 observations, 5 are 268 cm, 5 are 259 cm, 5 are 248 cm, and 5 are 246 cm.
c. Out of 30 observations, 28 are 276.65 cm, 1 is 276.9 cm, and 1 is 277.0 cm.
d. Out of 20 observations, 5 are 281 cm, 5 are 286 cm, 5 are 291 cm, and 5 are 298 cm.