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:
| Crew | Open 1st VIII | Open 2nd VIII | Open 3rd VIII | U16 1st VIII | U16 2nd VIII | U16 3rd VIII | U15 1st IV | U15 2nd IV | U15 3rd IV | U15 4th IV | U15 5th IV | U15 6th IV |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1994.0 | GT | BBC | GT | BGS | BGS | GT | BGS | BBC | BGS | BGS | GT | GT |
| 1995.0 | BGS | GT | GT | BGS | BGS | GT | GT | BGS | BGS | BGS | TSS | GT |
| 1996.0 | GT | BGS | BGS | GT | BBC | BGS | TSS | GT | BGS | BGS | BGS | BGS |
| 1997.0 | BGS | GT | GT | BGS | GT | BGS | ACGS | TSS | GT | GT | BGS | ACGS |
| 1998.0 | ACGS | TSS | BGS | BGS | ACGS | BGS | ACGS | TSS | BGS | TSS | TSS | TSS |
| 1999.0 | BGS | GT | ACGS | ACGS | ACGS | BBC | ACGS | BGS | BGS | BGS | BGS | BBC |
| 2000.0 | TSS | TSS | TSS | TSS | BBC | BBC | BBC | ACGS | BGS | BGS | BGS | ACGS |
| 2001.0 | BGS | GT | GT | BBC | BGS | ACGS | BBC | ACGS | BBC | BBC | BGS | BBC |
Question:
what are all the open 1st viii with u15 4th iv being gt
Answer:
BGS