This is the 505th most frequent Hebrew word.
שלהן
"Their" or "theirs" (feminine plural).
In this sentence, "שלהן" means "their" and refers to possession, denoting that the excellent results belong to the girls.
הבנות הציגו את התוצאות המצוינות שלהן בכיתה.
The girls presented their excellent results in class.
Here, "שלהן" means "their own" and emphasizes that the business uniquely belongs to the women.
הנשים פתחו עסק משלהן בתחום האומנות.
The women started their own business in the field of art.
In this case, "שלהן" means "their" and clarifies ownership of the cars.