To divide 1 liter by 4 milliliters, you first need to convert 1 liter to milliliters, since 1 liter is equal to 1000 milliliters.
Now you perform the division:
\[ \frac{1000 \text{ ml}}{4 \text{ ml}} = 250 \]
So, 1 liter divided by 4 milliliters equals 250.