The diagram at right again shows the same cylindrical wire as the diagrams above. This time, the diagram includes a green integration path that is a circle of radius r. In the questions below, assume that you integrate counter clockwise around this integration path. 4. Write an expression for the line integral illB- til as you integrate counter clockwise around the integration path. Express the answer in terms of B and r. ifs. af=| '3?ch | 5. Write an expression for the current that is enclosed by the integration path. Express your answer in terms of I, r and R. 15. Use Ampere's Law to derive an expression for the magnitude of the magnetic field at a distance r from the center of the wire. Express your answer in terms of I, r, R and the constant #9