more p-chem

Explain why each of the following integrals must be 0 when the functions are hydrogen -like wavefunctions:
<2p1|Lz|3p-1> and <2p0|Lz|2p0>
Show that taking the lithium spin orbitals in a Slater determinant as 1sa,
1sb, and 1s(c1a+c2b) where c1 and c2 are constants gives a wavefunction that equals zero.
the a and b are alpha and beta
this problem also has the 2p0 but I thought the p orbital had -1 0 and 1