Problem $2$

Consider a variant Turing machine in which the head of the reader can

either stay put or move to the right.

$($a$)$ Describe why this is not equivalent to a normal Turing machine.

$($b$)$ What class of languages does this machine recognize? Briefly

describe why.

Consider a variant Turing machine that has three independent heads.

At each step, the Turing machine can choose which of the three heads

to move. Only one head can move in each step. Each head is still

not allowed to move left. Prove that such a machine can simulate a

normal Turing machine.

Please be as thorough as possible. For proving something with Turing Machines, provide an algorithm first. For the class of languages problem please provide a concrete class of languages and a proof. Thank you, promise to thumb up for full answers