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2- Rayleigh density is given as: (\"c\" is a real constant) f(x) = [x / c2 ] exp( -x2 / (2 c2) ) u(x) where u(x) is unit-step function The kurtosis of a distribution is often measured by means of quantity B = E{(x-1,L)4} / 64 , evaluate B for Rayleigh Density. Do not use Gamma Function formulas for moments of Rayleigh p.d.f. The formulas of the moments (depending on \"'c\") should be proven explicitly by integration by part with other necessary properties