Answer
$\beta=0.10$
Work Step by Step
To find the speed parameter $\beta$, remember that beta is equal to $$\beta=\frac{v}{c}$$ where $c$ is the speed of light, $c=3.0\times 10^8m/s$. The velocity must be in meters per second, so dimensional analysis must be performed. $$\frac{3.0\times 10^4km}{1s}\times \frac{1.0\times 10^3m}{1km}=3.0\times 10^7m/s$$ Substituting the known value of $v=3.0\times 10^7m/s$ and $c=3.0\times 10^8m/s$ yields a speed parameter of $$\beta=\frac{3.0\times 10^7m/s}{3.0\times 10^8m/s}=0.10$$