Option 4 DHS 2.2

DHS 2.2
№.4. Given the vector. It is necessary: ​​a) to calculate the mixed product of the three vectors; b) find the module of the vector product; c) calculate the scalar product of two vectors; d) check whether the two vectors are collinear or orthogonal; e) check whether the three vectors will be coplanar. a (-7; 0; 2); b (2; -6; 4); c (1; -3; 2).
No. 2.4. The vertices of the pyramid are at points A (2; 4; 1); B (–3; –2; 4); C (3; 5; –2); D (4; 2; –3). ..........
No. 3.4. The force F (–4; 5; –7) is applied to the point A (4; –2; 3). Calculate a) the work force in the case; when the point of its application; moving straight; moves to point B (7; 0; –3); b) the modulus of the moment of force relative to point B.