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:
| Number | District | Size km² | Population | Density hab/km | Councilman | Party |
| --- | --- | --- | --- | --- | --- | --- |
| 1.0 | Ciutat Vella | 4.49 | 111290.0 | 24786.0 | Carles Martí i Jufresa | CiU |
| 2.0 | Eixample | 7.46 | 262485.0 | 35586.0 | Assumpta Escarp i Gibert | C iU |
| 3.0 | Sants-Montjuïc | 21.35 | 177636.0 | 8321.0 | Immaculada Moraleda i Pérez | CiU |
| 4.0 | Les Corts | 6.08 | 82588.0 | 13584.0 | Montserrat Ballarín i Espuña | CiU |
| 5.0 | Sarrià-Sant Gervasi | 20.09 | 140461.0 | 6992.0 | Katty Carreras-Moysi | CiU |
| 6.0 | Gràcia | 4.19 | 120087.0 | 28660.0 | Ricard Martínez i Monteagudo | CiU |
| 7.0 | Horta-Guinardó | 11.96 | 169920.0 | 14217.0 | Elsa Blasco i Riera | CiU |
| 8.0 | Nou Barris | 8.04 | 164981.0 | 20520.0 | Carmen Andrés Añón | C iU |
| 9.0 | Sant Andreu | 6.56 | 142598.0 | 21737.0 | Sara Jaurrieta | CiU |
| 10.0 | Sant Martí | 10.8 | 221029.0 | 20466.0 | Francesc Narváez | CiU |
Question:
what is the size km² when the density hab/km is 8,321?
Answer:
21.35