Table:
Date	Working time	TWA-S [ppbv]
Beginning	End
October 27th 2009	02:00 pm	10:00 pm	45.1
October 27th 2009	10:00 pm	06:00 am	22.1
October 28th 2009	06:00 am	02:00 pm	8.3
October 28th 2009	02:00 pm	10:00 pm	23.9
October 28th 2009	10:00 pm	06:00 am	18.7
October 29th 2009	06:00 am	02:00 pm	17.1

Convert the image into Markdown format.

| <ROWSPAN=2> Date | <COLSPAN=2> Working time | <ROWSPAN=2> TWA-S [ppbv] | 
 | Beginning | End | 
 | --- | --- | --- | --- | 
 | October 27th 2009 | 02:00 pm | 10:00 pm | 45.1 | 
 | October 27th 2009 | 10:00 pm | 06:00 am | 22.1 | 
 | October 28th 2009 | 06:00 am | 02:00 pm | 8.3 | 
 | October 28th 2009 | 02:00 pm | 10:00 pm | 23.9 | 
 | October 28th 2009 | 10:00 pm | 06:00 am | 18.7 | 
 | October 29th 2009 | 06:00 am | 02:00 pm | 17.1 |