(a) Explain the design and operational differences between the 1" generation and the 2nd generation CT scanners. [6 marks] (b) In a CT scan, four successive sets of x-rays produced total attenuations for a 3 x 3 matrix of a human tissue as shown in figure 2. Use the algebraic image reconstruction method to reconstruct the image of the tissue. [14 marks] 2nd set 3rd set 4th set 1st set 11 20 10 23 20 14 19 18 Figure 2: Total attenuations of x-rays of a CT scan (c) Discuss the advantages and disadvantages of the iterative and analytic reconstructions methods. 15 marks]