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:
| Rank | Athlete | Country | Time | Notes |
| --- | --- | --- | --- | --- |
| 1.0 | Ondřej Synek | Czech Republic | 6:50.23 | SA/B |
| 2.0 | Tim Maeyens | Belgium | 6:52.70 | SA/B |
| 3.0 | Peter Hardcastle | Australia | 7:00.09 | SA/B |
| 4.0 | Andrei Jämsä | Estonia | 7:05.48 | SC/D |
| 5.0 | Wang Ming-Hui | Chinese Taipei | 7:17.08 | SC/D |
| 6.0 | Law Hiu Fung | Hong Kong | 7:29.21 | SC/D |
Question:
What is the highest rank for a 6:52.70 time and notes of sa/b?
Answer:
2.0