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                let osoby=["Jan Nowak","Kazimierz Zyga","Stefan Koc","Ewa Mocek","Mariusz Abramski"];
/* Metoda .splice() zmienia zawartość tablicy, 
- usuwając wskazane elementy 
- dodając nowe elementy.
Metoda .splice() zwraca tablicę zawierającą usunięte elementy. 
Jeżeli usunięty został tylko jeden element, zwracana jest tablica jednoelementowa */
/* Linia wyświetli tablicę usunietych elementów - w naszym przypadku 3 element
Jeden element zostanie usunięty, dwa dodane. */
console.log(osoby.splice(3,1,"Maria Kapik","Elżbieta Konf"));

// Linia wyświetli aktualny stan tablicy, po usunięciu elementu i 
// dodaniu dwóch nowych.