What are the domain and range of the piecewise function below? 

a. domain: all real numbers except x = 0, x = 2, and x = 6
range: all real numbers
b. domain: all real numbers except x = 0, x = 2, and x = 6
range: all real numbers except y = 0
c. domain: all real numbers except x = 6
range: all real numbers
d. domain: all real numbers except x = 6
range: all real numbers except y = 0