Помогите, пожалуйста. Я не знаю, где использовать past simple, а где present perfect

1 Italy won the World Cup in 2006.
He's happy because States United have won all their matches this year.
2 Can you tidy your room? I have tidied it this morning.
Can you tidy your room? I have tidied it.
3 What time did you arrive home last night?
Has Ben arrived? Yes, he's in the living room.
4 Come on, let's eat. Dad has cooked dinner.
Who has cooked this food? It's delicious.
5 I have met lots of interesting people since I arrived.
Did you meet anyone interesting while you were on holiday?