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:
| Stop no. | Platform | Line | Stopping pattern | Destination |
| --- | --- | --- | --- | --- |
| [2778] Claisebrook Station platforms | [2778] Claisebrook Station platforms | [2778] Claisebrook Station platforms | [2778] Claisebrook Station platforms | [2778] Claisebrook Station platforms |
| 99021 | 1 | Armadale / Thornlie | All stations | Perth |
| 99022 | 2 | Armadale / Thornlie | All stations, B, C, T | Armadale or Thornlie |
| 99023 | 3 | Midland | All stations | Perth |
| 99024 | 4 | Midland | All stations, A, B, P | Midland |
Question:
What is Stop No., when Destination is Perth, and when Line is Midland?
Answer:
99023.0