Misc: from what is welsh rarebit made?

Questions

Groups: A group of unicorns is called a ----------. A group of kangaroos is called a mob. A group of whales is called a pod. A group of geese is called a gaggle. A group of owls is called a parliament. A group of ravens is an unkindness. A group of crows is a murder. A group of bears is called a sleuth. Twelve or more cows is called a flink.?

---------- were domesticated around 4,000 years ago.?

Camels were used as pack animals in ---------- and Arizona as late as 1870.?

The hippopotamus gives birth ---------- and nurses its young in the river as well, although the young hippos must come up periodically for air.?

The hippopotamus has skin an inch-and-a-half thick, so solid that most ---------- cannot penetrate it.?