CREATE TABLE table_19908313_2 (primary_sponsor_s_ VARCHAR, crew_chief VARCHAR)

Who is the primary sponsor for crew cheif Rick Ren's team?
SELECT primary_sponsor_s_ FROM table_19908313_2 WHERE crew_chief = "Rick Ren"
SELECT "primary_sponsor_s_" FROM "table_19908313_2" WHERE "Rick Ren" = "crew_chief"