4) If you use a simple row (instead of the Revolution slider) without full-height option then the preview is ok https://prnt.sc/1j1wys1
Revolution slider loads a number of additional styles and scripts, so I would not recommend using that if you just need the simple image in that section. Use the Row with the background (like on the example I did). If emulators are not very important for you then enable full-height option https://prnt.sc/1j1yxhl If you need a nice view of the emulator then disable that option and change the row padding to bigger.
When I check your site using the mobile device I don’t see any issues with the image even if the full-height option is enabled.
