When blood is half saturated by CO, partial disassociation cureve of Oxygen shifts to left
Explanation:
The affinity of CO with heamoglobin is greater than affinity of oxygen. When CO is present, oxygen is given off off less easily than when CO is not present.
It was outlawed in 1804, and it not only declared the colonies free of Britain but it helped to inspire Vermont to abolish slavery in its 1777 state constitution. Hope this helps.