Physics lab write up

Questions:
1. Derive the final expression from the theory section using torque instead of force.
2. What is the net force on the wires in the balance that run parallel to the solenoid?
3. Devise another way to run this experiment without using a mass on the other end of the balance, but still using a current balance.
4. Why must we wait until the balance is parallel with the table to calculate the magnetic field? If it was balanced (i.e. not moving) but at an angle, could we still find the magnetic field?