On the trip, Jerry had his cruise control set at 60mi/h for 4 hours.

1. Find slope

2. Positive, negative, zero, or undefined

We are given that Jerry had his cruise control set at 60mi/h for 4 hours.

The rate of change is the second name of slope.

We are given rate of 60 miles per hour.

Thereofore, slope would be just 60.

And because it's keep 60 miles per hour for next 4 hours that is constant for next four hours.

Therefore it would stay positive.

So, we can say

1. Slope = 60

2. Positive.