1103077007
Level:
B
In a triangle \( ABC \), \( a:b=1:2 \) and the measure of the angle \( BAC \) is \( 30^{\circ} \). Determine the size of the smallest interior angle of the triangle.
\( 30^{\circ} \)
\( 20^{\circ} \)
\( 10^{\circ} \)
\( 90^{\circ} \)