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1 1.2.7-T Question Help 7 The following data represent the muzzle velocity (in feet per second) of rounds red from a 155-mm gun. For each round, two measurements of the velocity were recorded using two different measuring devices. resulting in the following data. Complete parts (a) through (d) below. Observation 1 2 3 4 5 6 la A 791.9 794.4 790.8 791.5 793.4 793.8 B 796.1 794.2 798.5 787.4 795.3 790.1 (a) Why are these matched-pairs data? 9' A. The same round was red in every trial. B. The measurements (A and B) are taken by the same instrument. C. All the measurements came from rounds red from the same gun. _* D. Two measurements (A and B) are taken on the same round. (b) Is there a difference in the measurement of the muzzle velocity between device A and device B at the or = 0.01 level of signicance? Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. Let di =Ai - Bi. Identify the null and alternative hypotheses