How long have the pyramids in Egypt survived? (how old are they)
Of the 15 tallest dams in the U.S., most of them are made not of
cement, but of what?
Everything that man designs carries within it, the seeds of its own _ _
_ _ _ _ _ _ _ _ _ .
Most people call it "rusting", but the aging of metal by chemicals is
How often is the Golden Gate Bridge painted?
Which part of a suspension bridge will fail first?
How long does paper last?
In libraries, who (or, what)
eats the books?
What predatory animal lives in the Roman Coloseum?
Dogs become more like what animal?
Humans have used the world's oceans as a pantry and a _ _ _ _ _ _.
What happened to North Atlantic fish populations during World War 2?
How have landfills helped Seagulls?
What begin to fall after 200 years?
What caused the bridge in Pennsylvania to fall over? (the immediate cause; not the corrosion)
How does sea level help the Empire State Building fall?
What happens to the size of steel when it rusts?
After 1000 years, how much evidence of humans would be left?
Previously human areas become what color?
Where are our radio signals going?
In 10,000 years after people, what will be left to show that humans
Which human made monument lasts the longest?
If all of Earth's history were 24 hours, how long would humans have
been on Earth?