Find the distance if mr. nichols had been able to drive straight from the entrance to his campsite

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

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?

If a is a nonzero real number then the reciprocal of a is