3. Suppose f (y) is a probability density function (pdf). Let mm) = f: {Maa where f('")(y) is the rth derivative of y). (a) When f is pdf of N (a, 02), please nd R( f (2)) so that we are able to obtain the bandwidth based on normal scale rule. (b) Show that under some conditions, Rom) = (1)? foo Mommy. Which kinds of conditions do we need here?I Does stande normal distribution satisfy these conditions