 Hi and welcome to the session. Let us discuss the following question. The question says a heap of wheat is in the form of a cone whose diameter is 10.5 meters and height is 3 meters. Find its volume. The heap is to be covered by candles to protect it from rain. Find the area of the candles required. Let's now begin with the solution. We will first write down the given information. We are given that diameter of cone is 10.5 meters. As diameter is equal to 10.5 meters, therefore radius of cone is equal to 10.5 by 2 meters. And this is equal to 5.25 meters. We are also given that height of cone is equal to 3 meters. Now let's see what we have to find. We have to find volume of the cone and then we have to find area of the candles required. Let's first find volume of the cone. We know that volume of a cone is equal to 1 by 3 pi r square h. We know the value of r in h. So we can easily find volume by substituting values of r in h in this. We get 1 by 3 into 22 by 7 into 5.25 into 5.25 into 3 meter cube. Cancel 3 from both numerator and denominator. On cancelling 5.25 by 7, we get 0.75. On simplifying this, we get 86.625 meter cube. So volume of cone is 86.625 meter cube. Now look at the question. The question says the heap is to be covered by canvas to protect it from rain. Find the area of the canvas required. Heap is in the form of a cone and we have to cover this cone by a canvas. So clearly this means we have to cover only its rounded surface. So clearly area of canvas required is equal to surface area of cone. We know that the surface area of cone is equal to pi rl. We don't know the value of l. So we will now find value of l. l is equal to square root of h square plus r square. In the question, we are given that height is equal to 3 meters and we know that its radius is equal to 5.25 meters. So on substituting values of h and r, we get square root of 9 plus 27.5625. Now this is equal to 36.5625 under the rule and this is equal to 6.0467 approximately. Now we know the value of r and l. So we can now easily find curve surface area. So let's now substitute the value of r and l. Pi is equal to 22 by 7. r is equal to 5.25 meters and l is equal to 6.0467 whole meters square. Now this is equal to 99.825 meters square. So area of canvas required is 99.825 meters square. Enzyme required answers are 86.625 meter cube and 99.825 meters square. So this completes the session. Bye and take care.