CREATE TABLE table_8400 ("Brigade" CLOB, "Staffing" CLOB, "Type" CLOB, "Location" CLOB, "Pumpers" FLOAT, "Tankers" FLOAT, "Telebooms" CLOB, "Platforms" CLOB, "Cars" CLOB, "Hazmat" CLOB)

Which Tankers have a Hazmat of , and Platforms of , and a Staffing of volunteer?
SELECT "Tankers" FROM table_8400 WHERE "Hazmat" = '–' AND "Platforms" = '–' AND "Staffing" = 'volunteer'
SELECT "Tankers" FROM "table_8400" WHERE "Hazmat" = '–' AND "Platforms" = '–' AND "Staffing" = 'volunteer'