Which sentence uses a semicolon correctly?
Mrs. Lundey noted that half the class was out with the flu; therefore, she
postponed the exam until next week.
Our plane was delayed for two hours because of the storm therefore, we
missed our connecting flight,
All of her short life; Ruth had wanted to be a surgeon and do dramatic life-
saving surgeries for patients.
Even though the sweatshirt was tattered and tom; our little dog loved to
curl up in it at night to sleep.