Vectors A, B, C lie in XY plane and their resultant is R . The...

Vectors $\mathbf{A}, \mathbf{B}, \mathbf{C}$ lie in XY plane and their resultant is $\mathbf{R}$. The magnitudes of $\mathbf{A}, \mathbf{B}$ and $\mathbf{R}$ are 100,200 and 200 respectively. The angles made by these vectors with the positive direction of X axis are $60^{{}^{{}^{\circ}}}$, $150^{{}^{{}^{\circ}}}$, and $90^{{}^{{}^{\circ}}}$ respectively. Therefore, the magnitude and the angle made by $\mathbf{C}$ with positive direction of X axis respectively are