Mock Paper 14 Aug 2025 23:39

\[ \begin{array}{l} \text{$A, B, C$ and $D$ are points on a circle such that $ABCD$ is a square.} \\ \text{The square has side length } 4.2\,\text{cm.} \\ \text{Calculate the circumference of the circle. Give your answer correct to 1 decimal place.} \\ \text{You must show all your working.} \end{array} \]