a)
g: x = [0, 0, 0] + r·[3, 12, 4]
h: x = [0, 2, 5] + r·[0, 8, 10]
N = [3, 12, 4] ⨯ [0, 8, 10] = [88, -30, 24] = 2·[44, -15, 12]
[0, 0, 0] + r·[3, 12, 4] + s·[44, -15, 12] = [0, 2, 5] + t·[0, 8, 10] --> r = - 88/461 ∧ s = 6/461 ∧ t = - 517/922
|6/461·[44, -15, 12]| = 6/461·√2305 = 0.6248644104 LE = 62.49 m