$2.$ Suppose we wish to compute x y$,$ where x$,$ y are real numbers and might stand for $+,,\backslash$times $,-$:$.$

Let xA$,$ yA be the numbers used in calculation, and let xT $,$ yT be the true numbers. Suppose

$|$RE$($xA$)|,|$RE$($yA$)|1.$ Then, which two of the following can happen?

$($a$)|$RE$($xA $+$ yA$)|$ max$\{|$RE$($xA$)|,|$RE$($yA$)|\}$

$($b$)|$RE$($xA $$ yA$)|$ max$\{|$RE$($xA$)|,|$RE$($yA$)|\}$

$($c$)|$RE$($xA $\backslash$times yA$)|$ max$\{|$RE$($xA$)|,|$RE$($yA$)|\}$

$($d$)|$RE$($xA $-$: yA$)|$ max$\{|$RE$($xA$)|,|$RE$($yA$)|\}$