B. Tell whether the following material is useful or harmful. Write your answer on the blank before the number. 1. Used drinking straws made into lanterns 2. Dried leaves thrown into the canal 3.burning old rubber slippers 4. Using empty glass jars as sugar containers 5. Old car tires made into swings 6. Plastic containers turned into plant pots 7. Giving to neighbours expired vitamins 8. Scattering broken glasses 9. Storing spoiled milk in refrigerator 10. Leaving insecticide containers anywhere​