Trace the ONE-PASS construction of the B-tree for the sequence {M,C, P,H,G,X, S,U, 0, A,W}. Draw the configuration of the B-tree after inserting each letter. We use t = 2 as the branching degree threshold of the B-tree, so that: (1) all the non-root node must have at least t-1=1 key and at most 2t - 1= 3 keys; and (2) The root node of an non-empty B-tree must have at least one key and at most 2t - 1 = 3 keys