Eu errei?

//1
function helloWorld(){
    console.log("hello world");
}
helloWorld();

//2
function helloworld2(desafio2){
    console.log(`Olá ${desafio2}` );
}
helloworld2("desafio2");

//3
function double(numero){
    console.log(numero *2);
}
double(10);

//4
function media(n1,n2,n3){
    console.log((n1 + n2 + n3)/3);
}
media(10,20,30);

//5
function mostnumber(n1,n2){
    if(n1>n2){
        console.log(n1);
        return n1;
    }
    else{
        console.log(n2);
        return n2;
    }
}
function randomNumber(){
    return parseInt(Math.random() * 10 + 1);
}
let random1 = randomNumber();
let random2 = randomNumber();

console.log(random1, random2);

mostnumber(random1,random2);

//6
function numberXNumber(numero){
    console.log(numero * numero);
}
numberXNumber(10);