What does each logging statement print, why?

excercise.js

// What does each logging statement print, why?

var x = 1;
console.log(x);
if(1) {
    var x = 2;
    console.log(x);
}
console.log(x);

var x = 10;
function foo(x) {
    if(!x) {
        x = 4;
    }
    console.log(x, arguments);
};
foo.call(7);

var foo = (function() {
    console.log(x);
})();
foo(5);