(a)\(m \lambda=2 a sin \theta_b\)

\(\lambda=\frac{2 a sin \theta_b}{m}=\frac{2(1/300mm)sin10^0}{1}=0.00116mm=1.16\mu m\)

(b)\(sin \theta=\frac{m \lambda}{a}=2sin \theta_b\)

\(\theta=sin^{-1}(2 sin 10^0)=20.322^0\)

\(P.F.=\frac{a cos \theta}{mf}=\frac{(1/300mm)cos20.322^0}{(1)(170cm)}=1.84nm/mm\)