What is the volume of the cone

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?

Combine like terms to make a simpler expression 3z+z

Write two point-slope equations for the line passing through the points (6, 5) and (3, 1)