11. What is the speed of the ball that moves to about 10 meters in 2 seconds? A 5 m/s B. 20 m/s C. 1 m/s D. 50 m/s 12. A beetle crawls 2 cm/minute for ten minutes. How far did it crawl? A 8 centimeters C. 20 centimeters B 5 centimeters D. 30 centimeters 13. A duck flies 60 meters in 10 seconds. What is the duck's speed? A 600 m/s B. 6 m/s C. 50 m/s D. 70 m/s 14. Which of the following DOES NOT belong to the group? A. aluminum C. copper B. plastic D. iron 15. Some materials which allow an electric current to flow through them are called electricity A insulators C. conductors B convectors D. radiators 16. Materials that block an electric current from flowing are called A insulators C. conductors B. convectors D. radiators 17. Why are electric wire usually made up of copper? A. Because copper is a good insulator B. Because copper is a good conductor C. Because copper is a poor insulator D. Because copper is a poor conductor 18. Which is the best conductor of electricity? A. aluminum C. gold B. copper D. silver 19. You can protect yourself from the harmful effects of conductors by using A conductors C. convectors B. insulators D. radiators 20. Which among the following materials is useful in cooking food?​