Consider the planes 3.1," -l 2y l 4z : land 3.9: l 4z : 0. (A) Find the unique point Pon the yaxis which is on both planes. ( 0 , a 0 ) (B) Find a unit vector u with positive first coordinate that is parallel to both planes. 3 4 4. . 77 + +77 u 51 0_] 45k (C) Use parts (A) and (B) to find a vector equation for the line of intersection of the two planes. :03): gr i+ % j+llk A million years ago, an alien species built a vertical tower on a horizontal plane. When they returned they discovered that the ground had tilted so that measurements of 3 points on the ground gave coordinates of (0, 0, 0), (2, 3, 0), and (0, 2, 3). By what angle does the tower now deviate from the vertical? - radians