To convert milliliters to liters, you can use the conversion ratio of 1 liter = 1,000 milliliters.
To find out how many liters are in 6,750 milliliters, you can divide the number of milliliters by 1,000:
\[ 6,750 , \text{milliliters} \div 1,000 = 6.75 , \text{liters} \]
So, the cylinder holds 6.75 liters.