Calculating Magnetic Field in a Circular Circuit with Varying Resistivity

[rraj411]

Homework Statement

In the ATTACHMENT is the given circuit. Which contains two resistance
R1 and R2 in form of circle of radius r = 1 m with a battery
having e.m.f. V = 10∏ volt. Upper resistance is having
resistivity = 4Ω-m & lower resistance having resistivity =
2Ω-m. Angle between two points A and B is 60°. (wires have
same cross section A1 = A2 = 2 cm2)
Find magnitude of magnetic field at centre.

The attempt at a solution
I tried it using the formula B = μiθ/4∏r. BUT THE ANSWER IS NOT COMING CORRECT.

 

[mfb]

BUT THE ANSWER IS NOT COMING CORRECT.

Please don't write in caps.
What did you get for the currents in both parts of the circle?
Which field strength did you get, and do you know the correct answer?
Note that the currents will be different in the two sides. And you have to take their length into account.