Find the number of distinct triangulations of the following polygons:
a) Polygon P contain n+3 vertices V0=(0,0) V1=(1,0) ...Vn=(n,0) Vn+1=(1,1) and Vn+2=(0,1) labeled in the counter-clockwise order.

b) a) Polygon P contain n+4 vertices V0=(0,0) V1=(1,0) ...Vn=(n,0) Vn+1=(2,1) and Vn+2=(1,1) Vn+3=(0,1)labeled in the counter-clockwise order.

c)b) a) Polygon P contain n+5 vertices V0=(0,0) V1=(1,0) ...Vn=(n,0) Vn+1=(3,1) and Vn+2=(2,1) Vn+3=(1,1) Vn+4=(0, 1)labeled in the counter-clockwise order. Note that ^2 = 1/6(n)(n+1)(2n+1)