2023 ACSBR EM S1 EOY P2 Q8

Calculate the interior angle of a regular nonagon (nine-sided polygon).[2]

The diagram shows a composite figure made up of a semicircle and a trapezium \({PQRS}\). \({QOR}\) is the diameter of the semicircle with centre \({O}\). \(PQ=18\) m, \(RS=10\) m, \(PS = 15\) m, \(QR = 17\) m. Editorial completion of the omitted instruction: calculate the total area of the composite figure.[3]

The diagram shows a triangular prism. Given that the volume of the prism is \({111.39\ \mathrm{cm}^3}\), calculate the total surface area of the prism.[3]