To calculate the rate of change in the plane's altitude, we can use the formula for rate:
\[ \text{Rate} = \frac{\text{Change in altitude}}{\text{Time}} \]
In this case, the change in altitude is 4,000 feet (the plane is descending, so the change will be negative) and the time it takes to make this adjustment is 3.5 minutes.
Substituting the values into the formula:
\[ \text{Rate} = \frac{-4000 \text{ ft}}{3.5 \text{ min}} \]
Now, calculating this:
\[ \text{Rate} = -1142.857 \text{ ft/min} \]
Rounding this to the nearest hundred:
\[ \text{Rate} \approx -1100 \text{ ft/min} \]
Thus, the rate of change in the plane's altitude is approximately -1100 feet per minute.