To use the formula for radian measure, you must first have the radius and the arc length in the same units, so you must convert one of them. Now

$\displaystyle{\left(\frac{{{2}\pi}}{{9}}\ \text{ yards}\right)}\cdot{\left(\frac{{{3}\ \text{ feet}}}{{{1}\ \text{ yard}}}\right)}=\frac{{{2}\pi}}{{3}}\ \text{ feet}\usepackage{cmbright}\Huge\$ , so:

$\displaystyle\theta=\frac{{s}}{{r}}=\frac{{\frac{{{2}\pi}}{{3}}\ \text{ ft}}}{{{2}\ \text{ ft}}}=\frac{{{2}\pi}}{{3}}\cdot\frac{{1}}{{2}}=\frac{\pi}{{3}}\usepackage{cmbright}\Huge\$