Answer:
f(T) = 400*T + 850
Explanation:
We dont need to see the function to know the equation of your problem.
We know that the climbing rate is
400 ft/ min
This means that for each passing minute, the plane is 400 feet higher in the air.
We are also told that the airport is 850 ft above sea level
This is the starting elevation for the plane.
The problem can be described by a line with the following form.
f(T) = 400*T + 850
Where T is the time in the minutes after departure.
Please see the graph of the equation below.