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:
| Block | Launched | Operational | Not usable | Retired | Launch Failures |
| --- | --- | --- | --- | --- | --- |
| Block I | 11.0 | 0.0 | 0.0 | 10.0 | 1.0 |
| Block II | 9.0 | 0.0 | 0.0 | 9.0 | 0.0 |
| Block IIA | 19.0 | 8.0 | 1.0 | 10.0 | 0.0 |
| Block IIR | 13.0 | 12.0 | 0.0 | 0.0 | 1.0 |
| Block IIRM | 8.0 | 7.0 | 0.0 | 1.0 | 0.0 |
| Block IIF | 4.0 | 4.0 | 0.0 | 0.0 | 0.0 |
| Total | 64.0 | 31.0 | 1.0 | 30.0 | 2.0 |
Question:
What is the highest number of not usable satellites when there are more than 0 launch failures, less than 30 retired, and the block is I?
Answer:
0.0