Atomic Radius Questions

If 'a' stands for the edge length of the cubic systems: simple cubic, body centred cubic and face centred cubic, then the ratio of radii of the spheres in these systems will be respectively:

Lithium metal crystallises in a body centred cubic crystal. If the length of the side of the unit cell of lithium is $351\text{pm}$, the atomic radius of the lithium will be:

Copper crystallises in a face-centred cubic lattice with a unit cell length of $361\text{pm}$. What is the radius of copper atom in $\text{pm}$?

Identify the wrong statement in the following: