A rod of weight $\text{W}$ is supported by two parallel knife edges $\text{A}$ and $\text{B}$ and is in equilibrium in a horizontal position. The knives are at a distance $\text{d}$ from each other. The centre of mass of the rod is at distance $\text{x}$ from $\text{A}$ . the normal reaction on $\text{A}$ is: