Answer
(a) $675~nm=6.75\times10^{-4}~mm$
(b) $675~nm=2.66\times10^{-5}~in$
Work Step by Step
See conversion factors (inside front cover).
$1~nm=10^{-9}~m$, $1~mm=10^{-3}~m$ and $1~in=2.54\times10^{-2}~m$
(a) $675~nm=(675~nm)(\frac{10^{-9}~m}{1~nm})(\frac{1~mm}{10^{-3}~m})=675\times10^{-6}~mm=6.75\times10^{-4}~mm$
(b) $675~nm=(675~nm)(\frac{10^{-9}~m}{1~nm})(\frac{1~in}{2.54\times10^{-2}~m})=266\times10^{-7}~in=2.66\times10^{-5}~in$
