CREATE TABLE table_28728 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

Who was the incumbent in the Ohio 10 district?
SELECT "Incumbent" FROM table_28728 WHERE "District" = 'Ohio 10'
SELECT "Incumbent" FROM "table_28728" WHERE "District" = 'Ohio 10'