So if instead we wanted to basically move the sodium from this side to this side, this value would have been positive. And so a Delta G in this case would have been positive. But because our Delta G is negative, we're basically moving from this side to this side. And that means no energy must be inputted into that molecule to move it in that direction. So what that means is this will be passive transport, not active transport. And finally, now that we know what concentration gradient is and electro gradient is, we can basically combine these two concepts into a single concept.