Sand is discharged from the silo at $A$ at a rate of $50 \mathrm{kg} / \mathrm{s}$ with a vertical velocity of $10 \mathrm{m} / \mathrm{s}$ onto the conveyor belt, which is moving with a constant velocity of $1.5 \mathrm{m} / \mathrm{s}$. If the conveyor system and the sand on it have a total mass of $750 \mathrm{kg}$ and center of mass at point $G,$ determine the horizontal and vertical components of reaction at the pin support $B$ and roller support $A .$ Neglect the thickness of the conveyor.