What is the value of "x" after the following code runs? var x; x++;

What will be printed to console? function Foo(){ var foo = 1; bar = 'hello' } var f = new Foo; console.log(f.foo,bar);

Which Array prototype method actually modifies the array it's been called on?

What will be printed in console? var i = function(){ return 10; }(); console.log(i());

Consider the following variable assignments: var a = 144; var p = 3; The operation a >> p yields the same result as:

Consider the following variable assignment: var s = Math.random(9,100); the variable s is:

What's the output? if we call f(3)? const f = (x, y = true) => x * y;

What is TypeError?

What will be the value of a? let a = -1 ? 'foo' ? null : -1 : 1;

What does ~ mean in bitwise operation?

Valid states of the created Promise?