How research examiners go about examining a thesis?

Hey all! I am pursuing my PhD in Environmental and resource economics from Ohio State University, in Columbus, United States. I am at the last stage of my course. I submitted my thesis 3 months ago and I am waiting for my viva now and I am pretty nervous about my thesis too.

• What if they reject my work?
• How do the examiners make decision?
• What ‘weight’ do they give?

So, yeah, I am pretty curious and writing to simply ‘know more’!