CHICAGO (AP) _ Grain futures were mostly lower Tuesday on the Chicago Board of Trade. Dec. corn was off 6.75 cents at $5.36 a bushel. Dec. wheat lost 11 cents at $7.16 a bushel. Dec. oats gained 11.25 cents at $4.14 a bushel. Nov. soybeans was down 2 cents at $13.25 a bushel. Beef was...