Grains and the soy complex prices were mixed, but not much changed overnight. They weakened, though, during the day session as the U.S. dollar strengthened. Weekly export sales volumes for old crop corn and soybeans were a little higher than expected. General Comments What markets give, markets can take away. The U.S. dollar rebounded from a 10-week low with the U.S. Dollar Index gaining back 0.7 percent. The bounce was partially technical and also in response to a favorable report on weekly unemployment claims that helped offset yesterday's pessimism on jobs. Tomorrow's jobs report from the Labor Dept. will trump all other inputs on the subject and probably direct how the U.S. currency finishes the week. For today, however, the U.S. doll...