Hi,

Lots of geometry questions! The area of a cylinder is Pi*Radius^2*Height. A cylinder is like a bunch of circles stacked on top of each other and that is where the height comes in. So in this case (to find the volume) you need to find the area of the circle: (.5^2)*Pi and multiply that by the height of 5. So the volume is 5/4PI cubic feet. That's how much sand you need to fill the cylinder. Now, you know that the sand weighs 200Kg per cubic foot. So, multiply 200 by 5/4Pi and you get 250Pi Kg.

Let me know if this makes sense to you.

HG.

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