Final answer:
The Biot-Savart law can be used to calculate the magnetic field produced by a current. In this case, we need to parametrize the surface of the parallelogram and write down the Biot-Savart integral for the magnetic field in terms of integration parameters and constants.
Step-by-step explanation:
The Biot-Savart law is used to calculate the magnetic field produced by a current. In this case, we need to parametrize the surface of the parallelogram as r'(s,t).
The top and bottom edges are at t = +1/2 and -1/2, and the left and right edges are at s = +1/2 and -1/2.
The Biot-Savart integral for the magnetic field can be written as an integration of the parameters s, t, and the constants r₀, ℓ, and w.