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:
| Week | Date | Opponent | Result | Attendance |
| --- | --- | --- | --- | --- |
| 1 | September 15, 1974 | New York Jets | W 24–16 | 74,854 |
| 2 | September 22, 1974 | at Oakland Raiders | L 27–7 | 48,108 |
| 3 | September 29, 1974 | at Houston Oilers | W 17–7 | 28,538 |
| 4 | October 6, 1974 | Denver Broncos | L 17–14 | 67,298 |
| 5 | October 13, 1974 | Pittsburgh Steelers | L 34–24 | 65,517 |
| 6 | October 20, 1974 | at Miami Dolphins | L 9–3 | 67,779 |
| 7 | October 27, 1974 | at San Diego Chargers | W 24–14 | 34,371 |
| 8 | November 3, 1974 | New York Giants | L 33–27 | 61,437 |
| 9 | November 10, 1974 | San Diego Chargers | L 14–7 | 48,551 |
| 10 | November 18, 1974 | at Denver Broncos | W 42–34 | 50,236 |
| 11 | November 24, 1974 | at Cincinnati Bengals | L 33–6 | 49,777 |
| 12 | December 1, 1974 | at St. Louis Cardinals | W 17–13 | 41,863 |
| 13 | December 8, 1974 | Oakland Raiders | L 7–6 | 60,577 |
| 14 | December 14, 1974 | Minnesota Vikings | L 35–15 | 35,480 |
Question:
how many opponents were played twice that season?
Answer:
3