[填空题]
The following diagram shows part of the(/gz yuyx9- tham. ag.hh*b ,d graph of3l5 oz mgo0,c ,3lvklq f(x)=$x^{3}-3 x^{2}-4 x+ 12$, $x \in \mathbb{R}$ . The shaded region R is bounded by the x -axis, y -axis and the graph of f .
1. Write down an integral for the area of region R ；[Area A]=$\int_{-2}^{0}\left(x^{3}-a x^{2}-4 x+b\right) \mathrm{d} x$;a= ,b=
2. Find the area of region R is units$^2$
A parallelogram A B C D has four vertices with the coordinates shown as below.
3. Find the value of a , the y -coordinate of points $\mathrm{B} $ and $ \mathrm{C}$ , such that the area of the parallelogram is equal to the area of region R . a= .
