Finished the exercise, and for kicks, I'm now trying to actually call the function and calculate the circle area and perimeter.

Code:

```
function Circle (radius) {
this.radius = radius;
this.area = function () {
return Math.PI * this.radius * this.radius;
};
// define a perimeter method here
this.perimeter = function() {
return 2 * Math.PI * this.radius;
};
}
var newCircle = new Circle(5);
console.log(this.perimeter, this.area);
```

I used newCircle to construct an object, and gave it a radius of 5, but I can't actually log the area and radius to the console.

Both return as "undefined".

Help please?