Misc: The tail end of the spinal cord?

Questions

In 1776 Amedeo---------- , made famous by picking 6.022 x 10 ^ 23 ?

In 1778 Capt. ---------- passes through Bering Strait. ?

In 1778 Capt. Cook passes through ---------- Strait. ?

In 1842 The US-Canada border defined by the ---------- -Ashburton Treaty. ?

In 1842 The US-Canada border defined by the Webster----------- Treaty. ?