Mensuration (Pyramid, Cones and Spheres) - Volume and Surface Area of Composite Solids

A solid rubber safety barrier has a uniform cross-section consisting of a rectangle topped by a semicircle, as shown (not drawn to scale). The rectangular portion is \(1.2\) m wide and \(0.8\) m high. The barrier is \(2.0\) m long. The semicircular portion extends along its entire length.

Length perpendicular to this end view: \(2.0\) m

1. Calculate the volume of rubber used to make the barrier.

   [3]

2. Before installation, the whole exterior is coated with a protective finish, including the underside and both ends. Calculate the area to be coated.

   [4]

Give both answers to \(3\) significant figures.