Oil prices reached a nine-month high amid concerns about tight oil supplies after Russia and Saudi Arabia extended supply cuts. Brent futures, a global benchmark to measure oil prices, rose to $91.01 a barrel on Friday, according to MarketWatch, and sits at $90.44 a barrel as of Sunday morning. Prices had already surged last week after Riyadh and Moscow agreed to extend supply cuts beyond October. The U.S. banned Russian oil imports last year, but Russia and Saudi Arabia respectively produced 11% and 12% of the world's oil last year, according to the Energy Department, so any changes in production...