The formula for the circumference of a circle is $\displaystyle{C}=\pi{d}\usepackage{cmbright}\Huge\$ . The diameter of the circle is 2 inches, so $\displaystyle{d}={2}\usepackage{cmbright}\Huge\$ .

$\displaystyle{C}=\pi\cdot{2}={2}\pi\usepackage{cmbright}\Huge\$ inches