Consider the following demand function for good X: Q$=9-0\mathrm{.}1$p$\_$x$-$p$\_$y$+0\mathrm{.}01$p$\_$z$+0\mathrm{.}001$Y $,$

where Own Price, p$\_$x$=$$$30$

Price of a related good, p$\_$y$=$$$4$

Quantity demanded $=24\mathrm{.}75$

Price of a related good, p$\_$z$=$$$275$

Consumer income, Y$=$$$20,000$

$($a$.)$ The income elasticity of demand $\backslash$xi when equilibrium quantity is $24\mathrm{.}75$ units and income is $$20,000$ is equal to