Which general function does lactase perform

Which of the following is the main purpose of a human community?

Which feature of a human community is similar to a niche in a biological community

The scales shown in the introduction measure mass, or the amount of matter in a particular object. the scientific law of conservation of mass states that matter cannot be created or destroyed during a chemical reaction, but it can change from one form to another. did the simulation support this scientific law? explain why or why not.