You need a set of choices to select.
I can convert the measure 3/4 inch to centimeters, so if the set of choices are in centimeters you can select the closest one.
1 inch = 2,54 cm
[3/4 inch] * 2,54 cm/inch = 1,905 cm ≈ 1,90 cm
So, the answer is a number similar to 1,90 cm.
