Question

4)The letter ... arrived yet.
A) hasn't
B) didn't
C) don't
D) aren't

5)I ... in London since i was ten years old.
A)live
B)lived
C) have lived
D)am lived​

Answer 1

4) The letter hasn't arrived yet.
The letter – it, поэтому hasn't. Yet – указатель времени Present Perfect

5) I have lived in London since I was ten years old.
Апелляция к длинному процессу. Since – указатель времени Present Perfect.