[Kwant] Unit of Energy in conductance vs Energy plots

Dear all, 1. In the example of KWANT, there is a conductance vs Energy plot. In this plot, the unit of Energy is mentioned as [t]. what does t signify? is it in eV? 2. In the band structure of zig-zag graphene lead, there are upper and lower parts in the band structure. which one is the conduction band? I'm attaching a figure for 2nd question. figure https://drive.google.com/file/d/1dmhZkSOWu4ERvMfP855vgbYpAyt5NTcn/view?usp=s...