Which of these was a result of the empancipation proclaimtion

1. in which sentence is the underlined portion a predicate nominative? for astronauts, going into space to repair orbiting equipment becomes a challenge. for astronauts, going into space to repair orbiting equipment becomes tricky. for astronauts, going into space to repair orbiting equipment becomes challenging. for astronauts, going into space to repair orbiting equipment becomes frequent.

Which two former presidents continued to work in government after leaving the white house, and in what capacity?

Which sentence is punctuated correctly? the shoes normally cost 40 dollars, however; we got them on sale. the shoes normally cost 40 dollars however we got them on sale. the shoes normally cost 40 dollars, however, we got them on sale. the shoes normally cost 40 dollars; however, we got them on sale.