Misc: what word may be used to refer to a group of elks??

Questions

In 1728 Johann---------- , Swiss mathematician, proved pi is irrational ?

In 1791 ---------- Fitch granted a US patent for his working steamboat ?

In 1791 John ---------- granted a US patent for his working steamboat ?

In 1847 ---------- was proclaimed an independent republic. ?

In 1883 ---------- began erupting with increasingly large explosions. ?