How many UK OUNCES IS 300 ml?

Answer 1

Ounces are a measure of mass whereas ml are a measure of volume, so the two cannot be converted without knowing the density of the substance that makes up the 300 ml.

However, if you meant what is 300 ml in imperial FLUID ounces, then:

28.4 ml ≈ 1 fl oz

→ 300 ml ≈ 300 ÷ 28.4 fl oz ≈ 10.6 fl oz