Direction of curve shift unclear without graph Steps:

• Oxygen dissociation curves shift based on hemoglobin's affinity for O2, influenced by pH via the Bohr effect.
• A right shift (decreased affinity) aids O2 unloading during exercise; a left shift (increased affinity) retains O2.
• During exercise, CO2 and lactic acid typically decrease pH, causing right shift and decreased affinity.
• Without graph details on whether exercise curve is left or right of rest curve, factors cannot be identified.

Not enough information.

Final answer: Not enough information.