Two point sources which are separated by $1\mathrm{.}5$ mm emit light of wavelength $650$

nm$.$ Assume that the resolution is diffraction limited$,$ and your eyes have circular

apertures of diameter $3$ mm$.$ What is the maximum distance for you from the point

sources such that you can still resolve them as two point sources. $(3$ marks$)$

$($b$)$ If the two point sources emit light of shorter wavelength, how will the answer in

part $($a$)$ change? Increase, decrease, or remain the same? $(2$ marks$)$