What is the azimuthal quantum number (also called the angular-momentum quantum number), ℓ, for the orbital shown here?

(the photo is a d orbital. it has 4 balls around it)

Express your answer numerically as an integer.

2 answers

I can't see the photo but a d orbital has a value of 2 for ell (I can't write the script ell and the lower case l looks like (OK, ALMOST like) the number 1).(see 1 vs l)
s orbitals have ell = 0
p orbitals have ell = 1
d orbitals have ell = 2
l=2