Driving in the United States and Europe is picking up a little. Refineries in China are buying more oil as that country’s economy reopens. Saudi Arabia and Russia ended their price war and slashed production, and American oil companies are decommissioning rigs and shutting wells. All those developments have helped push up oil prices modestly in recent weeks. On Friday, U.S. oil futures climbed more than 7 percent to nearly $30 a barrel, which is just enough for some of the best oil wells in the United States to break even. That may seem like a minor miracle given that the price is more than $60 above where it was about a month ago. On April 20, the U.S. oil futures contract fell below zero for the first time as some traders paid buyers to take oil off their hands […]