Question

Two power lines lie parallel to each other, separated by 20 cm.They carry parallel currents, both of
magnitude 3000 A.
a) Find the force per unit length on one line due to the current inthe other line. Is the force attractive or
repulsive?
b) Consider a point P lying halfway between the two lines.
- What is the magnitude of the magnetic field at P due to the twocurrents?
- If the currents in the two lines were antiparallel, what would bethe magnitude of the magnetic field
at P?

Please help me!!!!Thank you so much