How many paragraphs should be there in an expository essay?

Dogs make wonderful pets because they us stay happy and healthy. the topic sentence is "dogs make wonderful pets." , is this correct? i keep doubting myself.

I’m robert frost poem “mending wall”, what does the narrator have on his side of the wall? a. a pine forest b. a cow farm c. an apple orchard d. a rabbit nursery

My pretty rose tree by william blake a flower was offered to me, such a flower as may never bore; but i said, ‘i’ve a pretty rose tree,’ and i passed the sweet flower o’er. then i went to my pretty rose tree, to tend her by day and by night; but my rose turned away with jealousy, and her thorns were my only delight. what is the rhyme scheme of the two stanzas in this poem? a. abba, cdda b. abab, acac c. abab, cddc d. abaa, cddc