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3. An aluminum wire having a cross-sectional area equal W to 4.00 X 10 5 m- carries a current of 5.00 A. The den- sity of aluminum is 2.70 g/cm. Assume each alumi- num atom supplies one conduction electron per atom. Find the drift speed of the electrons in the wire.5. A proton beam in an accelerator carries a current of 125 pA. If the beam is incident on a target, how many protons strike the target in a period of 23.0 s?16. A 0.900-V potential difference is maintained across a 1.50-m length of tungsten wire that has a cross- sectional area of 0.600 mm-. What is the current in the wire?53. A certain toaster has a heating element made of M Nichrome wire. When the toaster is first connected to a 120-V source (and the wire is at a temperature of 20.0"C), the initial current is 1.80 A. The current decreases as the heating element warms up. When the toaster reaches its final operating temperature, the cur- rent is 1.53 A. (a) Find the power delivered to the toaster when it is at its operating temperature. (b) What is the final temperature of the heating element