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:
| Date | Round | Opponent | Venue | Result | Attendance |
| --- | --- | --- | --- | --- | --- |
| 5 Jan | Three | Chasetown | A | W 3 - 1 | 2420.0 |
| 27 Jan | Four | Hereford United | A | W 2 - 1 | 6855.0 |
| 16 Feb | Five | Wolverhampton Wanderers | H | W 2 - 0 | 15339.0 |
| 9 Mar | Quarter Final | Middlesbrough | A | W 2 - 0 | 32896.0 |
| 6 Apr | Semi Final | Barnsley | N | W 1 - 0 | 82752.0 |
| 17 May | Final | Portsmouth | N | L 0 - 1 | 89874.0 |
Question:
What round has hereford united as the opponent?
Answer:
Four