[Ger-Poland-Volhynia] Help with Ethnic Surname Origins

[John Smith]

I would like to determine the ethnic origins of the surnames listed below.
I think they are Ukrainian, Russian or Polish, but they could also belong
to another ethnicity. I have also included first names which may be helpful
in determining ethnicity. Thanks so much for any insight.

Petr and Hana Roshczinski

Juri Zhilka

Leonid Mosendz

Nila Khaseviczova