2022 ACSI EOY P2 Q4

The traffic cone shown below is made of solid material. It consists of a cone of height \(40\) cm and diameter \(18\) cm placed on top of a cuboid that measures \(40\) cm by \(40\) cm by \(2\) cm. Calculate the mass of the cone, correct to the nearest kg, if the material used to make the cone has a density of \(1.2\) g/cm\(^{3}\).

(Volume of cone \(= \frac{1}{3}\pi r^2h\), Curved surface Area of cone \(= \pi r l\) where \(r\) is radius, \(h\) is height, and \(l\) is the slant height of the cone)

The diagram below shows a right pyramid with a regular pentagonal base of side \(8\) cm, centre \(O\) and the vertical height, \(VO\), is \(20\) cm. \(M\) is the mid-point of \(AB\).

Calculate,