Answer from cs61c-ed (Cory Benavides 14101530) for Question 1
A preprocessor simply searches and replaces text in the program with predefined code.  Usually we use this to save time writing code or to keep track of constants that may be changed one day.  The product is still a C file.  The compiler is the next step, as it is the first component that begins translating the higher-level language code to lower-level code