1. A copper wire, drawn to the right, has a hollow core. The outer radius of the wire is 1.0mm and the radius of the hollow, air-filled core is 0.50 mm. [10 points] a. Calculate the cross-sectional area of the wire (consider only the copper outside the core) in m²? [ 4 pts] b. If a current of 1.0A runs through the wire, what is the current density of the wire? [3 pts] c. Copper has an electron density of around 8.5×10²8 electrons/m³. About how fast do electrons move down the length of the wire? [3 pts]

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