$8.$ Chapter $13,$ modified version of Question $19$: Using the definition of the function Nlog presented in the text $($i$.$e$.$ Nlog x$=$r ln$$r$/$x$),$ determine Nlog$($xy$)$ and Nlog$($x$/$y$)$ in terms of Nlog x and Nlog y $($as well as another term that is the Nlog of a constant$).$ Show that your product & quotient formulas are correct by computing Nlog$($xy$)$ and Nlog$($x$/$y$)$ for x $=20$ and y $=5$ with r $=0\mathrm{.}9.$ Start with Nlog xy$=$r ln$$r$/$xy$.$ This can be related to Nlog x and Nlog y by multiplying both numerator and denominator by r and then using the laws of logarithms. $(5$ points$)$