Answer:
-3.6 degrees
Explanation:
Since we need to find the temperature that is 3 miles above ground we first need to multiply the distance above ground by the decrease in temperature per mile.
3 * 5.2 = 15.6
Now that we have the total decrease in temperature at that altitude we subtract it from the temperature at ground level. This gives us the final temperature at 3 miles above the ground.
12 - 15.6 = -3.6
Finally, we can see that the temperature is -3.6 degrees