Examples: Construct examples of the thing(s) described in the following. Try to find examples that are different than any in the reading.
(a) The graph of a function with $f(4)=2$ that has a removable discontinuity at $x=4$
(b) The graph of a function that is continuous on its domain but not continuous at $x=0$.
(c) The graph of a function that is continuous on (0,2] and (2,3) but not on (0,3) .