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:
| Year | Driver | Constructor | Location | Formula | Report |
| --- | --- | --- | --- | --- | --- |
| 1960.0 | Jack Brabham | Cooper - Climax | Roskilde Ring | Formula 2 | Report |
| 1961.0 | Stirling Moss | Lotus - Climax | Roskilde Ring | Formula 1 | Report |
| 1962.0 | Jack Brabham | Lotus - Climax | Roskilde Ring | Formula 1 | Report |
| 1963.0 | Peter Revson | Cooper - BMC | Roskilde Ring | Formula Junior | Report |
| 1964.0 | Hartvig Conradsen | Cooper - BMC | Roskilde Ring | Formula Junior | Report |
| 1965.0 | Kurt Ahrens Jr. | Brabham - Ford | Roskilde Ring | Formula 3 | Report |
| 1968.0 | Ingvar Pettersson | Tecno - Ford | Roskilde Ring | Formula 3 | Report |
| 1973.0 | Randy Lewis | Brabham - Ford | Roskilde Ring | Formula 3 | Report |
| 1974.0 | Jac Nelleman | GRD - Ford | Jyllandsringen | Formula 3 | Report |
| 1975.0 | Jac Nelleman | GRD - Ford | Jyllandsringen | Formula 3 | Report |
| 1976.0 | Jac Nelleman | Van Diemen - Toyota | Jyllandsringen | Formula 3 | Report |
| 1977.0 | Jac Nelleman | Chevron - Toyota | Jyllandsringen | Formula 3 | Report |
| 1995.0 | Toni Teittinen | Reynard - Mugen - Honda | Jyllandsringen | Formula 3 | Report |
Question:
What was the constructor in 1975?
Answer:
GRD - Ford