Misc: What do the broken chains at the bottom of the statue of liberty symbolise?

Questions

The average minimal speed of birds in order to remain aloft in flight is reported to be about 161/2 feet per second, or about ---------- miles per hour.?

Mussels can thrive in ---------- because of an inborn ability to purify bacteria, fungi, and viruses.?

Guinea pigs were first domesticated by the ----------, who used them for food, in sacrifices, and as household pets.?

The Hirudo leech has three jaws with 100 teeth on each jaw - making 300 teeth in all. The ---------- leech uses a different method of sucking blood. They insert a long proboscis into the victim as opposed to biting.?

The average porcupine has more than 30,000 quills. Porcupines are excellent swimmers because their quills are hollow and serve as pontoons to keep them ----------?