1. Given four points A1 (x1, y1, z1), A2 (x2, y2, z2), A3 (x3, y3, z3), A4 (x4, y4, z4)
 Be the equation:
 a) a plane A1A2A3; b) direct A1A2;
 c) direct A4M perpendicular to the plane A1A2A3;
 g) direct A3N, parallel line A1A2;
 d) a plane passing through the point perpendicular to the line A4 A1A2.
 Calculated:
 e) The sine of the angle between the line and the plane A1A4 A1A2A3;
 g) the cosine of the angle between the coordinate plane and the plane Oxy A1A2A3;
 1.13 A1 (4, 6, 5), A2 (6, 9, 4), A3 (2, 10, 10), A4 (7, 5, 9)

2. Solve the following tasks
 2.13 Write the equation of the plane through the origin perpendicular to the two planes 2x - 3y + z - 1 = 0 and x - y + 5z + 3 = 0

3. Solve the following tasks
 3.13 Check whether lie on a straight line point A (0, 0, 2), B (4, 2, 5) and C (12, 6, 11)