It's one-third of an ounce.
It's also two teaspoons--measured with a kitchen measuring teaspoon, not a regular teaspoon out of the drawer.
1 quart or 1 litre
488
10 US fluid ounces = 295.735296 milliliters
3.38 US fluid ounces
30cc=1oz so 100cc=3 1/3 oz