You will need:
1.Lego or mega blocks.
2.Pencils and erasers.
3.Ruled or scrap paper to find volumes.
5.For finding volumes, you should always check in the length, width and height.
7.Now start building the bottom or the bigger shape first out of Legos or mega blocks.
8.Once you have finished building, find the volume of the big rectangular figure and note it down.
9.Next build the smaller shape exactly the way you did the bigger shape.
11. And "Voila", you got the combined volume of the solid figure.