Is schedule S legal? Do transactions T₁, T₂ and T₃ observe the tree policy? Do transactions T₁, T₂ and T₃ observe the 2PL policy? Is schedule S serializable? Name the serial schedule to which S is equivalent.

BC DEF Ti lock(A) lock(B) unlock(A T2 T3 lock(A lock(C) unlock(B) lock(B) unlock(A) unlock(B) unlock(C) lock(C) lock(E) lock(F) unlock(E) unlock(F) unlock(C