Помогите,надо опеределить форму глагола past simple или present perfect.Можно только ответы)

11. Lucy has broken her leg, so she can’t come skiing. 12. Julie has arrived! Come and say hello! 13. They were cold when they arrived home. 14. Jack broke his arm when he felt off a horse in 2005. 15. I have known about the problem for months, but I haven't  found a solution yet. 16. A: When  did you arrive?      B: At 10 pm last night. 17. She has been a teacher for ten years, and she still enjoys it.  18. How long have you known Jill? I know you see her often. 19. I haven't seen the sea before. 20. A: Hello       B: Hi Mum, it’s me. I just wanted to say I have arrived safely and everything is fine.