[填空题]
A company is going to make an excavation tomctw xoxmoa.,y 7n5 u)w8u 3b+ access a mine. The c,zutge3l (f+yasuse,4vmy 0 3ost of excavating is \euu ss3zm( ,ltyg3 fe v40y,a+$ 12 per $\mathrm{m}^{3}$ . The following table shows an estimate of the areas of horizontal crosssections, at 5 -metre intervals, of the underground to be removed where the height is measured in metres below the ground level.
1. Use the trapezoidal rule to find an estimate of the volume of ground to be removed，we obtain the V ≈ m$^3$ (round number)
2. Hence, or otherwise, estimate the total cost of excavation;The total cost of excavation is $\$$ .
