What's the point of code around the variable statement: (function() { var a = true; })(); 

Which statement about Promises is not correct?

What will be the value of a? let a = void function f() { let a = 1 - 2; let b = 2 - 3 + 1; if (a) { return true; } else if (b) { return false; } else { return null; } return -1; }();

What is JavaScript?

Select the existing event handler for DOM elements.

What's the output? var x = [typeof x, typeof y][1]; console.log(typeof typeof x);

What is the value of x? var a = 'abc'; var x = a instanceof String;

What will this code produce: +new Date()

Values of x and y after the invocation of `foo` in following? var x = 'I am global x'; var y = 'I am global y'; function foo() { var y = x = 'Hello from foo'; } foo();

function foo() { this = 'foo'; } var a = foo(); What will the preceding code produce?

What's the output? var Apple = function() { var color = 'green'; var apple = { picked:false, pick: function() { this.picked = true; console.log (color); color = 'yellow'; }, change: function() { this.color = Math.random() > 0.5 ? 'yellow':'red'; } }; return apple; } var a = Apple(); a.pick(); console.log (a.color);