Question

Find the angular size of a circular object with a 3​-inch diameter viewed from a distance of 6 yards.

Answer 1

check picture below
thus $\bf tan(\theta)=\cfrac{sin(\theta)}{cos(\theta)}\qquad thus \\\\\\ tan(\theta)=\cfrac{3}{6}\implies tan(\theta)=\cfrac{1}{2} \\\\\\ \theta=tan^{-1}\left( \cfrac{1}{2} \right)$