DIRECTIONS:   In this applet, you create a rational C2 Bezier spline by placing control points p_i = (x_i,y_i) on the screen, which are stored as points in space as (1,x_i,y_i). The weights λ_i are initially set as 1, and are modified by using the A and Z keys. The A key decreases the weight and the Z key increases the weight. The algorithm for creating the composite rational Bezier curve proceeds by constructing a C1 Bezier spline in space with control points (λ_i,x_i,y_i) and then perspectively projecting this curve onto the plane (1,ξ,η).