Answer:
if the noun is singular, the apostrophe goes before the s. example: a farmer's crops. If the noun is plural, the apostrophe goes after the s: farmers' manure.
singular nouns are when it talks about one person, place, thing, or idea.
plural nouns are when it talks about more than one person place thing or idea.
Step-by-step explanation:
so in short terms, in the first sentence it talks about one farmer. in the second sentence it talks about more than one farmer.