Living things are made of four types of molecules, known as macromolecules. These macromolecules are proteins, nucleic acids (DNA and RNA), lipids (fats) and carbohydrates. Each type of macromolecule is made of its own building blocks, which are intricately connected to form different shapes.
The root beer exerts a force on all sides of the ice cream. These forces are all equal and cancel each other out. Gravity pushes downward on the ice cream. The ice cream floats because the buoyant force is greater than the weight of the ice cream.