In this exercise we consider several familiar processes. In each case, describe several common causes and several assignable causes that might result in variation of the given quality characteristic.
a. Process: getting ready for school or work in the morning. Quality characteristic: the time it takes to get ready.

b. Process: driving, walking, or otherwise commuting from your home or apartment to school or work. Quality characteristic: the time it takes to commute.
c. Process: studying for and taking a statistics exam. Quality characteristic: the score received on the exam.

d. Process: starting your car in the morning. Quality characteristic: the time it takes to start your car.