The motion of particle P on the elliptical path shown is defined by the equations x = (2 cos t ?? 1) / (2 ??cos

The motion of particle P on the elliptical path shown is defined by the equations x = (2 cos πt ?? 1) / (2 ??cos πt) and y = 1.5 sin πt/(2 ?? cos πt), where x and y are expressed in feet and t is expressed in seconds. Determine the radius of curvature of the elliptical path when

(a) t = 0,

(b) t = 1/3 s,

(c) t = 1 s.