In this problem, assume that the distribution of differences is approximately normal. Note : For degrees of freedom d . f . not in the Student's t table, use the closest d . f . that is smaller . In...

In this problem, assume that the distribution of differences is approximately normal.Note: For degrees of freedomd.f. not in the Student'st table, use the closestd.f. that issmaller. In some situations, this choice ofd.f. may increase theP-value by a small amount and therefore produce a slightly more "conservative" answer.

Suppose that at five weather stations on Trail Ridge Road in Rocky Mountain National Park, the peak wind gusts (in miles per hour) for January and April are recorded below.