4. Let A=[1,5,2] and B=[2,9,-1] Mark Value:12 a. Find AXB, and verify that AXB is perpendicular to both A and B b. Find A.B c. Find Proj(A on to B) d. Find A-B e. Find 3A-2B f. Find if a linear combination of A and B can be made to make vector C= [5,23,1]