Let the surface x + y + z = 2 separates air ( = o ) and a block of iron (=400 o ). The

Let the surface x + y + z = 2 separates air (μ =μ _o ) and a block of iron (μ=400μ _o ). The region x + y + z >2 is air where B ₁ =50 a _x + 30 a _y - 20 a _z Wb/m ^2. Find  B ₂ and H ₂ .