What uses who and whom correcctly Who loves science The class whom has the best projects will go on a trip Who is this package for?

The correct uses of "who" and "whom" in your examples are as follows: "Who loves science?" is correct because "who" is the subject of the verb "loves." In your second example, it should be "The class that has the best projects will go on a trip," since "that" is more appropriate for defining the subject. Lastly, "Who is this package for?" is correct, even though some grammarians might argue that "whom" could be used in more formal contexts; "who" is commonly accepted in everyday usage.