Figure 10.4 shows a famous example of the Sussman anomaly, a very early AI planning problem that was difficult for many early automated planning systems because they were non-interleaved. Given a conjunctive goal G1G2, a non-interleaved planner first solves G1 and then G2, or vice versa. (The resulting plan is the plan for G1 concatenated with the plan for G2, or vice versa.) (i) Represent 10.4 as a planning problem. (ii) Solve it by hand. (iii) Explain why this could be difficult for non-interleaved planners.