Let i be directed to the east, j be directed to the north, and k be directed upward. What are the values of products?

(a) i ∙ k

(b) (– k) ∙ (– j), and

(c) j ∙ (– j)? What are the directions (such as east or down) of products?

(d) k x j,

(e) (–i) x (– j), and

(f) (– k) x (–j)?