Wheat:  Net sales of 283,200 metric tons for 2019/2020 were down 1 percent from the previous week and 40 percent from the prior 4-week average. Corn:  Net sales of 494,000 MT for 2019/2020, primarily for Mexico (196,800 MT, including decreases of 11,700 MT), Japan (92,900 MT, including 4,500 MT switched from unknown destinations and decreases of 3,600 MT), unknown destinations (85,300 MT), Colombia (47,300 MT), and Thailand (39,400 MT), were partially offset by reductions for Nicaragua (1,000 MT).   Exports of 278,900 MT were primarily to Mexico (169,700 MT), Taiwan (27,200 MT), Japan (25,900 MT), Guatemala (22,600 MT), and the Dominican Republic (14,900 MT).     Soybeans:  Net sales of 1,038,000 MT...