Consider a new type of deterministic machine, having one read-only input tape and two stacks. The tape is read-only, it cannot be written, but the head can move left, right, or do nothing. Each stack operates, independently of the other, as in a deterministic pushdown automaton: M _ (K, ?, 1,1, 12,21, 22, ?, s) where K is a finite set of states, ? is a finite input alphabet, 11 and 12 are two finite stack alphabets (1,1 for the first stack, 12 for the second stack), zIE?and ze 12 are the initial symbols for the two stacks, s E K is the initial state. h is a special halting state not in K, just like in a Turig machine. (a) Give an appropriate definition for the transition function 6, for a configuration of this machine, for the "yields in one step" operator, and for the language accepted by this machine. (b) These machines can accept the same languages as a class of automata you already know deterministic pushdown automata, pushdown automata, or Turing machines? Prove your answer formally