Algebra 2!!

The equation of the piecewise function f(x) is below. What is the value of f(3)?

Sara can take no more than 22 pounds of luggage on a trip.her suitcase weighs 112 ounces.how many more pounds can she pack without going over the limit?

Let f(x) = 3 − x . find the average rate of change of f(x) from x = a to x = a + h and simplify your answer so that no single factor of h is left in the denominator.

Find the domain and range of the following function f(x) = 51x - 21+ 4