Misc: in an average lifetime, the average american ___ 410078 times?

Questions

Whose presidential competency was questioned when he insisted during a debate that there was no Soviet domination in Poland?

Between 1857 & 1861, during James Buchanan's presidency, what role was performed by his neice, Harriet Lane?

Which ex-president died in 1973, five days before an agreement was signed in Paris ending the fighting in Vietnam?

What roars in the 'roaring forties?

What Russian city's name translates to 'ruler of the east?