Problem 19. Try to change 4th character of a given string. Were you able to do it?

const str = "Please give Rs1000";
str[3] = 'Q';
console.log(str);  // not changed as string is immutable
str.replace('s', 'Q');
console.log(str);  // not changed as string is immutable

/*
Output:
    Please give Rs1000
    Please give Rs1000
*/