CREATE TABLE table_75226 ("Sport" TEXT, "Record" TEXT, "Nation" TEXT, "Date" TEXT, "Time  ( sec. ) " FLOAT)

Which nation had a time of 48.38?
SELECT "Nation" FROM table_75226 WHERE "Time (sec.)" = '48.38'
SELECT "Nation" FROM "table_75226" WHERE "Time (sec.)" = '48.38'