CREATE TABLE table_39884 ("Week" FLOAT, "Date" TEXT, "Opponent" TEXT, "Result" TEXT, "Attendance" TEXT)

Who did the Texans play when there were 70,724 people in attendance?
SELECT "Opponent" FROM table_39884 WHERE "Attendance" = '70,724'
SELECT "Opponent" FROM "table_39884" WHERE "Attendance" = '70,724'