Could you show explanation and working for this example

Let h > 0 and let P, (0, 0), Q, and be the three points on the pianar curve y = x2/2 at x = h, x = 0. and x = h, respectively, and let the centre of the circle passing through these three points be at (0, p(h)). (A) Calculate R E hlilgl p(h), from first principles using no formula from the Math 223 course. > + (B) Look up in a calculus text (or search for ' 'curvature of a graph") the formula for the curvature of an arbitrary function y = y(x), and use that to calculate the radius of curvature of y = x2/2 at x = 0. (G) Parameterize the curve, place it in the plane 2 = 0, and calculate the radius of curvature using the formulas given in class. (D) Assuming a > 0, find the equation for the graph ya(x) of the lower half of the circle centred at (0, a) and radius a. When approximating the parabola y = x2/2 with that circle, the error is Ea(x) := ya(x) y(x). Calculate the limits Ea(x) x3 Ea(x) ER (x) lim x>0 lim 7 x>O (there are two cases from a = R and a R)