Can u help me to understand and answer each question (a,b,c and d???????)

Question The model (P) below has been solved bv the SEP method according to a selection criterion of the separation variable. Two partial enumeration trees, in which some information {node numbers, ...j1 has been deleted, are reproduced below. MaxZ = 53.1 + BK; underthe constraints x1 + x25 5.5.151 + 9X: 5 12, I1 2 U, I: E D, I; et 1:; integers. For each enumeration tree: a] Calculate the optimal values (In) from the information provided in the trees in the gures below {if applicable}. by Build the sequence of separations, stating explicitlv, which nodes are discarded, which remain in a queue. :1 If applicable, describe the next separation: from which node fps} does the separation take place? what constraints are attached to [ph] on each of the branches emerging from (m)? a] Write explicitlv the linear model associated with this node (pk) at From which the next separation will take place. Arbre d'enumeration 1 Po: 30 = 41,25 x, = 2,25 X2 = 3,75 P: Z1 = 41 P : = = 39 X1 = 1,8 X=3 * =4 X=3 P3 PA: =4 = 40 5/9 non X = 1 realisable X2 = 4 4/9 P5: 35 = 37 P6: 36 = 40 X1=0 X=5Arbre d'enumeration 2 P : = = X) = 2,25 X, = 3,75 P : = = P: = = X=2 X> = 3,89 *, = 3 P:= = P : = = X1 = 2 X1 = 1,8 X2 = 3 X2 =4 P Non P: = = realisable P