The following data represent the muzzle velocity (in feet per second) of rounds fired 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
A 790.2790.2 791.3791.3 791.4791.4 793.7793.7 793.4793.4 793.3793.3
B 800.1800.1 789.7789.7 799.8799.8 792.6792.6 802.1802.1 788.5788.5

Required:
a. Why are these matched-pairs data?

1. Two measurements (A and B) are taken on the same round.
2. All the measurements came from rounds fired from the same gun.
3.The same round was fired in every trial.
4. The measurements (A and B) are taken by the same instrument.

b. Is there a difference in the measurement of the muzzle velocity between device A and device B at the α=0.01
c. Construct a 99% confidence interval about the population mean difference. Compute the difference as device A minus device B. Interpret your results.

d. Does this visual evidence support the results obtained in part(b)?

1. Yes, because 0 is contained in the boxplot.
2. No, because the boxplot is too large.
3. No, because 0 is not containednot containedin the boxplot.
4. Yes, because the boxplot shows no outliers.