In the Brinell test shown in the figure, a 10 mm hardened-steel ball is pressed into a steel specimen; the load and the two perpendicular indentation diameters measured under the microscope are given on the figure. Use the mean indentation diameter and HB = 0.102 × 2F/[πD(D − √(D² − d²))] with F in N and D, d in mm. Determine (a) the Brinell hardness number (answer in HB) and (b) the approximate ultimate tensile strength of the steel, taking UTS ≈ 3.45 × HB (answer in MPa).