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:
| NGC number | Object type | Constellation | Right ascension ( J2000 ) | Declination ( J2000 ) | Apparent magnitude |
| --- | --- | --- | --- | --- | --- |
| 6025 | Open cluster | Triangulum Australe | 16h03m42s | °30′00″ | 5.1 |
| 6027 | Interacting galaxy | Serpens | 15h59m12.7s | °45′47″ | 14.7 |
| 6027a | Interacting galaxy | Serpens | 15h59m11.5s | °45′14″ | 15.1 |
| 6027b | Interacting galaxy | Serpens | 15h59m11.0s | °45′42″ | 15.4 |
| 6027c | Interacting galaxy | Serpens | 15h59m12.1s | °44′47″ | 16.0 |
| 6027d | Spiral galaxy | Serpens | 15h59m13.2s | °45′33″ | 15.6 |
| 6027e | Interacting galaxy | Serpens | 15h59m15.1s | °45′55″ | 16.5 |
| 6043 | Interacting galaxy | Hercules | 16h005m01.2s | °46′26″ | 15.4 |
| 6087 | Open cluster | Norma | 16h19m | °56′ | 5.9 |
| 6093 | Globular cluster | Scorpius | 16h17m02.5s | °58′30″ | 8.7 |
Question:
what is the apparent magnitude of NGC number 6027d?
Answer:
15.6