A piece of timber has a cross-sectional Area A squared units perpendicular to its length and distance d units from its end as shown below. (d; A): (0;2.8),(2;4.7),(4;6.2),(6;7.3),(8;7.1),(10;6.7),(12;6.2) Draw a graph of A against d and use Simpson's rule with 12 intervals to find the volume of the piece of timber.​