What is the number of orbital's in a d sublevel

Five

Explanation:

The number of orbitals in a sublevel depends on the secondary quantum number l and the magnetic quantum number mₗ.

For a d subshell, l = 2.

The allowed values of mₗ are - 2, - 1, 0, 1, 2.

Since there are five allowed values of mₗ, there are five d orbitals.

Each d orbital corresponds to one of the five quantum numbers.