input question: Answer this question: what county is tacoma washington in????
output answer: Tacoma (, ) is a mid-sized urban port city and the county seat of Pierce County, Washington , United States.

input question: Answer this question: what is the title of Hobbes main work????
output answer: His 1651 book Leviathan established the foundation for most of Western political philosophy from the perspective of social contract theory.

input question: Answer this question: how does a dredge work?????
output answer: Developing this idea further, a motorized crane equipped with a drag bucket or clamshell (grabber) that is used to scoop material from the bottom of a body of water is also a dredger.

input question: Answer this question: what is the source of geothermal energy????
output answer:
The Geothermal energy of the Earth's crust originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%).