A shipment includes 900 pounds of a Table 2 flammable liquid and 200 pounds of another Table 2 hazard class. What placarding concept should you apply?

1. No placards because each material is under 1,001 pounds
2. Consider the aggregate gross weight of Table 2 materials, which may reach the placarding threshold
3. Only placard if one package weighs 1,001 pounds
4. Use Class 9 placards for all mixed loads