Given two lines in space, either they are parallel, they intersect, or they are skew (lie in parallel planes). In Exercises 65 and 66, deter- mine whether the lines, taken two at a time, are parallel, intersect, or are skew. If they intersect, find the point of intersection. Otherwise, find the distance between the two lines. 65. L1: x = 3 + 21, y = -1 + 4t, z = 2 = t; - L2: x= 1 + 4s, y = 1 + 2s, z = -3 + 4s; L3: x = 3 + 2r, y = 2 +r, z = -2 + 2r; -