Velocity of Winchester bullets. The American Rifleman reported on the velocity of ammunition fired from the FEG P9R pistol, a 9-mm gun manufactured in Hungary.

Field tests revealed that Winchester bullets fired from the pistol had a mean velocity (at 15 feet) of 936 feet per second and a standard deviation of 10 feet per second.

Tests were also conducted with Uzi and Black Hills ammunition.

a. Describe the velocity distribution of Winchester bullets fired from the FEG P9R pistol.

b. A bullet whose brand is unknown is fired from the FEG P9R pistol. Suppose the velocity (at 15 feet) of the bullet is 1,000 feet per second. Is the bullet likely to be manufactured by Winchester? Explain.

repeatedly sprayed with a 10% salt solution (B), and soaked in a 10% salt solution and dried (C).

a. Combine the mean (from Exercise 2.69) and standard deviation (from Exercise 2.90) to make a statement about where most of the permeability measurements for group A sandstone slices will fall. Which rule (and why) did you use to make this inference?

b. Repeat part a for group B sandstone slices.

c. Repeat part a for group C sandstone slices.

d. Based on all your analyses, which type of weathering

(type A, B, or C) appears to result in faster decay (i.e., higher permeability measurements)?