4. -What is the diameter of a 1 meter tungsten wire that has a resistance of 0.32 ohm?
5. -What is the resistance of a 4.5m copper wire that has a diameter of 1.5mm?
6. -What is the maximum power consumption of a 3V discman that drives a maximum current of 270mA?
7. -A microwave oven is designed to produce 3.3kw of heat when connected to a 240V source. What should your resistance be? 
8. - You buy a 75w electric bulb in Europe, where electricity is 240v. If you use that electric bulb in U.S.A. where the voltage is 120v. How will the brightness of the bulb change with respect to Europe?
9. -At a cost of $ 0.095 kw / hr. How much does it cost you to leave your backyard focus of 25w day and night for a year?