NEW YORK -- U.S. and EU sanctions have finally begun to bite very hard on Russia in the one place that matters most: energy. With the latest round of sanctions announced Friday, the Russians will now have to abandon the joint venture project they have inked with U.S. super-major Exxon Mobil Getting fossil fuels out of the ground is what energy companies do, but their stock price is reliant upon two related metrics -- how much it costs to get the oil out and also whether and how quickly they can increase the amount of oil and gas they produce.