Moderate -0.5 This appears to be an incomplete question fragment showing only a numbered list item. However, typical D1 sorting algorithm questions asking students to deduce properties of an original list from intermediate steps are straightforward applications of algorithm knowledge, requiring systematic reverse-working through bubble sort or quick sort passes with minimal problem-solving beyond careful bookkeeping.
(4 marks) - Using their 'sorted list' + choosing middle right pivots + discarding/retaining half the list. If their list is not in full alphabetical order M1 only.
**(a)** The list is not in alphabetical order. | B1 | (1 mark)
**(b)** E.g. A Quick sort
$$\begin{array}{ccccccccc}
J & M & C & B & T & H & K & R & G & F \\
C & B & G & F & H & J & M & K & R \\
C & B & F & G & H & J & M & K & T \\
B & C & F & G & H & J & K & M & R & T \\
B & C & F & G & H & J & K & M & R & T
\end{array}$$
Sort complete + named correctly | M1, A1, A1, A1=B1 | (4 marks) - Quick sort, pivots $p$, selected and first pass gives $<p, p, >p$ | First two passes correct, pivots chosen consistently for third pass | CAO sort completed correctly | 'Stop' + plus correct name for their sort - phonetically close
**(c)**
$$\text{Pivot 1} = \left\lceil \frac{1+10}{2} \right\rceil = 6 \text{ Jenny reject } 1-6$$
$$\text{Pivot 2} = \left\lceil \frac{7+10}{2} \right\rceil = 9 \text{ Richard reject } 9-10$$
$$\text{Pivot 3} = \left\lceil \frac{7+8}{2} \right\rceil = 8 \text{ Merry reject } 8$$
$$\text{Pivot 4} = 7 \text{ Kim - name found}$$ | M1 A1, A1ft, A1 | (4 marks) - Using their 'sorted list' + choosing middle right pivots + discarding/retaining half the list. If their list is not in full alphabetical order M1 only. | First pass correct is 6th item for a correct list (no sticky pivots) | Second and third passes correct is 9th and 8th items from a correct list (no sticky pivots) | CSO search complete + 'found'
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