 Hello and welcome to the session. I am Deepika here. Let's discuss the question which says in the given figure Einstein made of wood is in the shape of a cuboid with four conical depressions to hold pins. The dimensions of the cuboid are 15 centimeter by 10 centimeter by 3.5 centimeter. The radius of each of the depression is 0.5 centimeter and the depth is 1.4 centimeter. Find the volume of the wood in the entire stretch. Now we know that volume of cuboid is equal to length into breadth into height and volume of cone is equal to 1 by 3 pi r square h where is the radius? H is the height. So this is a key idea behind our question. We will take the help of this key idea to solve the above question. So let's start the solution. Now we are given length of the cuboid is equal to 10 centimeter. Weft of the cuboid is 10 centimeter and height of the cuboid is equal to 3.5 centimeter. Now a pen stand made of wood is in the shape of a cuboid with four conical depressions. Now the radius of the conical depression is equal to 0.5 centimeter. Now this is a conical depression and this radius is 0.5 centimeter and the depth of the conical depression equal to 1.4 centimeter that is the height of the cone is equal to 1.4 centimeter. Volume of wood is equal to volume of wood used in cuboid. This volume of four depressions is a conical. According to our key idea volume of cuboid is equal to length into breadth into height minus volume of cone is 1 by 3 pi r square h and this is equal to now length is 15 centimeter into breadth is 10 centimeter and height is 3.5 centimeter minus 4 into 1 by 3 into take pi is 22 upon 7 now radius is 0.5 centimeter and height is 1.4 centimeter. And this is again equal to 25 minus 4 into 1 by 3 into 22 upon 7 into 5 upon 10 into 5 upon 10 into 14 upon 10 centimeter cube and this is equal to 525 minus non-cancellation we have 1 into 2 upon 3 into 5 centimeter cube and this is again equal to 525 minus 22 upon 15 centimeter cube. This is equal to 525 minus now 22 upon 15 is 1.47. Hence the volume of wood used equal to 525 minus 1.47 and this is equal to 523.53 centimeter cube. Hence the answer for the above question is 523 0.53 centimeter cube. I hope the solution is clear to you. Bye and take care