I need some help with these two problems:

2. The coil in the figure carries current i = 2.39 A in the direction indicated, is parallel to an xz plane, has 6 turns and an area of 5.63 x 103 m, and lies in a uniform magnetic field B = (2.21 i - 3.58 j - 4.74 R) mT. (a) What is the magnetic potential energy of the coil- magnetic field system? (b) What is the magnetic torque (in unit-vector notation) on the coil? 28 A wire lying along an x axis from x = 0 to x = 0.944 m carries a current of 2.58 A in the positive x direction. The wire is immersed in a nonuniform magnetic field given by B = (4.15 T/m )x21 - (0.654 T/m )x ]. In unit-vector notation, what is the magnetic force on the wire