A cubic solid is made up of two atoms A and B. Atoms A are present at the corners and B at the centre of the body.
What is the formula of the unit cell ?

Explanation

To determine the formula of the unit cell for the given cubic solid made up of two atoms A and B, we will follow these steps:

### Step 1: Identify the positions of atoms in the unit cell
- Atoms A are located at the corners of the cubic unit cell.
- Atom B is located at the center of the body of the cube.

### Step 2: Calculate the contribution of atom A
- There are 8 corners in a cube.
...