1: Suppose that a natural draft cooling tower has the cross section below (a hyperbola). Suppose the tower is 460 feet wide at the base, 280 feet wide at the top, and 230 feet at its narrowest point (which occurs 330 feet above the ground.) Determine the height of the tower to the nearest foot.

2: The ellipse (x^2/3^2)+(y^2/6^2)=1 can be drawn with parametric equations where x(t) is written in the form x(t) = rcos(t) with r = ? and y(t) = ?

3: Suppose parametric equations for the line segment between (3,4) and (5,-9) have the form: {x(t) = a+bt

{y(t) = c+dt If the parametric curve starts at (3,4) when t=0 and ends at (5,-9) at t=1, then find a,b,c, and d.

4: A bicycle wheel has a radius R. Let P be a point on the spoke of a wheel at a distance d from the center of the wheel. The wheel begins to roll to the right along the x-axis. The curve traced out by P is given by the following parametric equations: {x(angle) = 15(angle)-10sin(angle)

{y(angle) = 15 -10cos(angle) What must we have for R and d?