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:
| Model | Specification | Build date | Total produced | Wheel arrangement | Prime mover | Power output |
| --- | --- | --- | --- | --- | --- | --- |
| FA-1 | DL-208A, DL-208B | 1949-1950 | 28.0 | B-B | 12-244B | hp (MW) |
| FB-1 | DL-209A, DL-209B | 1949-1950 | 20.0 | B-B | 12-244B | hp (MW) |
| FA-2 | DL-212, DL-212A | 1951–1953 | 45.0 | B-B | 12-244 | hp (MW) |
| FB-2 | DL-213, DL-213A | 1951–1953 | 21.0 | B-B | 12-244 | hp (MW) |
| FPA-2 | DL-212, DL-212A | 1953–1955 | 19.0 | B-B | 12-244D | hp (MW) |
| FPB-2 | DL-213, DL-213A | 1953–1955 | 14.0 | B-B | 12-244D | hp (MW) hp |
| FPA-4 | DL-218 | 1958–1959 | 34.0 | B-B | 12-251B | hp (MW) |
| FPB-4 | DL-219 | 1958–1959 | 12.0 | B-B | 12-251B | hp (MW) |
Question:
What is the build date of the locomotives with a total produced less than 45 and a fb-2 model?
Answer:
1951–1953