At 11:59 PM on December 31 the time square ball in New York city was 735 Feet above the ground one minute later it was 584 feet above ground which of the following gives the rate of change of the ball in feet per second

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?