To increase output in the short run, a specialist bicycle workshop adds units of labour (mechanics) to a fixed assembly space and toolset. The table below shows the relationship between the units of labour employed and the total daily output of assembled custom bicycles.
| Units of labour | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|
| Total daily output of bicycles | 6 | 15 | 28 | 46 | 66 | 83 | 95 | 101 |
At what point does the workshop first begin to experience diminishing marginal returns?
When the 5th unit of labour is employed
When the 7th unit of labour is employed
When the 6th unit of labour is employed
When the 8th unit of labour is employed
