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:
| Tie no | Home team | Score | Away team | Date |
| --- | --- | --- | --- | --- |
| 1 | Middlesbrough | 2–0 | Bolton Wanderers | 27 February 1978 |
| 2 | Derby County | 2–3 | West Bromwich Albion | 22 February 1978 |
| 3 | Wrexham | 1–1 | Blyth Spartans | 18 February 1978 |
| Replay | Blyth Spartans | 1–2 | Wrexham | 27 February 1978 |
| 4 | Queens Park Rangers | 1–1 | Nottingham Forest | 18 February 1978 |
| Replay | Nottingham Forest | 1–1 | Queens Park Rangers | 27 February 1978 |
| Replay | Nottingham Forest | 3–1 | Queens Park Rangers | 2 March 1978 |
| 5 | Bristol Rovers | 2–2 | Ipswich Town | 18 February 1978 |
| Replay | Ipswich Town | 3–0 | Bristol Rovers | 28 February 1978 |
| 6 | Millwall | 2–1 | Notts County | 18 February 1978 |
| 7 | Arsenal | 4–1 | Walsall | 18 February 1978 |
| 8 | Orient | 0–0 | Chelsea | 18 February 1978 |
| Replay | Chelsea | 1–2 | Orient | 27 February 1978 |
Question:
What away team has 7 as the tie no.?
Answer:
Walsall