Need help with the multiple choiceSolution5answer 4 A2A3A4

Need help with the multiple choice:

5)answer : 4 (A₂(A₃A₄))

explanation:- the no of scalar multiplications of 2 matrices M(p q), N(q r) is p*q*r, for (A₂(A₃A₄)) has minimum value

6)answer:1 and 4 are true

explanation:

1: X₃ means upto 3 values in X so its <A,L,G>

7)answer: 2, the length of a lcs of X₃ and Y₆ is 3

x₃ = <C,A,B> Y₆ =<A,\'C\',\'A\',D,\'B\',C>

lcs length = 3