Q11-12 pоints Cоnsider the pоset (D, | ), where D ={1, 2, 3, 6, 7, 14, 21, 42}. (Note: “ | ” is the symbol for “is divisible by”.) (а) Find аll lower bounds of 14 аnd 21 taken collectively. Do not find the lower bounds of 14 and 21 separately. (b) Find the greatest lower bound of 14 and 21 taken collectively. Do not find the greatest lower bound of 14 and 21 separately. (c) Determine the least upper bound of 14 and 21 taken collectively. Do not find the least upper bound of 14 and 21 separately. (d) Draw the Hasse diagram for this poset. (e) Determine the complement of each element of D in [D; ⋁ , ⋀ ]. (f) Is the lattice for [D; ⋁ , ⋀ ] a Boolean algebra? If so, why?