Out of the following set of forces, the resultant of which cannot be zero?

The resultant of two vectors $\overrightarrow{A}$ and $\overrightarrow{B}$ is perpendicular to the vector $\overrightarrow{A}$ and its magnitude is equal to half of the magnitude of vector $\overrightarrow{B}$. The angle between $\overrightarrow{A}$ and $\overrightarrow{B}$ is ___.

Two forces, each equal to $F$, act as shown in figure. Their resultant is,