A power line carries a current of 91 A west along the tops of 8.5-m-high poles.

a- What is the magnitude of the magnetic field produced by this wire at the ground directly below?Express your answer using two significant figures.

B=?T

b-What is the direction of the magnetic field produced by this wire at the ground directly below?What is the direction of the magnetic field produced by this wire at the ground directly below?

south

north

west

east

c-How does this compare with the Earth's magnetic field of about 1/2 G?Express your answer using one significant figure.

B_line/B_earth=?

c-Where would the wire's magnetic field cancel the Earth's field?Express your answer using one significant figure.

d=? m below the wire