0.01 Ml = One Unit. In measuring of insulin you may be asked to take 2 Units of Insulin, this means to take 0.02 mL of Insulin.
1cc=100units can also write as 1mL=100units, because 1cc=1mL
1 cc=100 units of Insulin so, 1 unit=0.01 cc Insulin
There are not a standard amount of units per ml, which makes this question unanswerable. For example, some drugs are 40,000 units per ml, whereas others may only be 1 unit per ml.
A unit of what?