The form of the equation is
y = m x + b
m is the rate of change
b is the initial value
let us use the data in the table to find m
Substitute it in the form of the equation above
To find b substitute x by 4000 and y by 43
Substitute it in the equation
Now substitute h by 5000 to find F
The temperature at altitude 5000 feet is 39 F
The answer is 39