Please show each step of your work and a brief explanation if applicable. Thanks in advance.

7. [2 marks] What is the domain and the range of the function that assigns each pair (i.e. 2- tuple) of positive integers to the first integer of the pair? [2 marks] Determine whether the following functions Z to Z is one-to-one: (a) ffn) -n-1 (b) (n) -n2 +1 8. 9. [2 marks] Determine whether he above function Z to Z is onto. 10. 12 marks] Let fx)x/31, FindftS) ifS 0, 1,2, 3, 4, 5,6) 11. [2 marks] Let a and b be the real numbers with a