Crude oil prices ended the week lower, with all eyes on the extent to which pledges on production cuts are being met. U.S. crude for February delivery settled down 64 cents, or 1.21%, at $52.37 a barrel on the New York Mercantile Exchange on Friday. Brent, the global benchmark, fell 56 cents, or 1%, to $55.45 a barrel on ICE Futures. U.S….