The correct answers with brief explanation:
Is broken into pieces
- The crust is indeed broken into different pieces, also known as plates, which moves according to the movement of magma.
Has seven main plates
- There are seven main plates indeed, namely the Pacific Plate, Indo-australian Plate, Eurasian Plate, Antarctic Plate, Africa Plate, South America Plate and North America Plate.
Is mostly made of silicon dioxide
- This is correct as the crust is made up of 59% silicon dioxide also known as silica.
Hope it helps!
