Which country is directly south of belarus?

The country directly south to Belarus is Ukraine.

When the Chernobyl disaster happened, the wind was blowing to the north and actually Belarus was more affected than Ukraine - this is because it is directly north of Ukraine, which means that Ukraine is directly south of Belarus.

I'm pretty sure it's c. extremely gradual but not 100% sure though.

Answer they are produced by collision of tectonic plates;