Yes. It looks like they share about 51 miles of common border, and I have one map that says it's dry land, not part of the lake.
Yes, the corner of Nigeria touches Chad, though the borders apparently meet in the middle of lake Chad, depending on the map.
Yes, Nigeria borders Chad on land, with roughly 51 miles of shared boundary, which is separate from Lake Chad. The land border is important for trade and geopolitical relations between the two countries. This geographical fact contributes to the understanding of regional dynamics in West Africa.
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