Given the intersecting lines: L1: x = 3t - 3, y = -2t, z = 6t + 7

L2: x = s - 6, y = -3s - 5, z = 2s + 1

a) Find the (acute) angle, rounded to the nearest degree, between the lines.

b) Find the point of intersection of the two lines

c) Find the equation of the plane containing the two lines.