Unless otherwise noted, the alphabet for all questions below is assumed to be (a,b). 1. [10 marks] This question asks you to examine the formal definitions of a TM and related concepts closely. B on these definitions, answer the following. (a) A configuration of a Turing Machine (TM) consists of three things. What are these three things? (b) Can input alphabet contain the blank symbol u? Why or why not? (c) The tape is infinite. Is the tape alphabet infinite? (d) Can a Turing machine's head ever be in the same location in two successive steps? (e) What is the difference between a decidable language and a Turing-recognizable language