useless trivia: What Word Means: A Nickel-copper Alloy?

Questions

The American ---------- weighs approximately one pound when fully grown.?

Mice, whales, elephants, giraffes, and humans all have seven neck ----------?

From crocodile farms, Australia exports about 5,000 crocodile skins a year. Most go to Paris, where a crocodile purse can sell for more than ----------?

Because the natural habitat of ---------- is of little use to man - the alkaline African lake waters support few fish and cannot be used for human consumption or irrigation - and also because their resting areas are typically inaccessible, the birds are rarely disturbed, unlike other African wild birds.?

The American opossum, a marsupial, bears its young just 12 to 13 days after conception. The Asiatic elephant takes 608 days to give birth, or just over ----------?