Answer
$r=2.14\times10^{9}ly$.
Work Step by Step
Use equation 44.14 to find the speed, with $\lambda_s=486.1 nm$, and $\lambda_o=563.9 nm$.
$$v=\frac{(563.9nm/486.1 nm)^2-1}{(563.9nm/486.1 nm)^2+1}c=0.14738c$$
Using equation 44.15, the distance is $r=\frac{v}{H_o}=2.03\times10^{25}m$.
Converting, $r=2.14\times10^{9}$ light years.
