Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Title | Director | Writer | Original airdate | Prod. Code |
| --- | --- | --- | --- | --- |
| "Pilot" | Andy Ackerman | Ken Levine & David Isaacs | August9,1993 | 40811-001 |
| "The Six Stages of Marshall" | Andy Ackerman | Ken Levine & David Isaacs | August16,1993 | 40811-002 |
| "Making Up Is Hard to Do" | Andy Ackerman | Larry Balmagia | August23,1993 | 40811-003 |
| "Dave's Big Wave" | Andy Ackerman | Dan Staley & Rob Long | August30,1993 | 40811-004 |
| "The Adventures of Ozzie and Marshall" | Andy Ackerman | Ken Levine , David Isaacs , Dan Staley & Rob Long | September6,1993 | 40811-005 |
| "The Old Men and the Sea (a.k.a. Him)" | Andy Ackerman | Ken Levine & David Isaacs | September13,1993 | 40811-006 |
Question:
Who wrote "The Six Stages of Marshall"?
Answer:
Ken Levine & David Isaacs