Vaping does have sometimes unknown chemicals and metals inside the nicotine containers that is not safe for lungs which can cause pop-corn lungs.
Answer 3 would probably be right
In the question about a recipe needing 4 ounces of milk to a 16 ounce recipe: 4 ounces of milk : 16 ounce recipe, 4/16 = 1/4 , 1/4 = 25/100 or 25%
The decimal amount ratio of milk to sauce is 25%
