which of these is direct labor

Stainless steel sheet metal $$6,523$

Rubber caps for bottles $3,284$

President's salary $4,752$

Shipping to customers $1,154$

Wages for equipment maintenance crew $2,865$

Insulation for bottles $1,141$

Stainless steel finishing solution $585$

Sandpaper $256$

Advertising expense $6,985$

Assembler wages $12,853$

Depreciation on office equipment $152$

Depreciation on milling machine $3,974$

Property tax for factory $1,554$

Pouring Supervisor Salary $3,258$