"What goes up must come down." You have probably heard that statement before. At one time this statement was true, but no longer. Since the 1960s, we have sent many spacecraft into space. Some are still traveling away from Earth. So it is possible to overcome gravity. Do you need a giant rocket to overcome gravity? No, you actually overcome gravity every day. Think about when you climb a set of stairs. When you do, you are overcoming gravity. What if you jump on a trampoline? You are overcoming gravity for a few seconds. Everyone can overcome gravity. You just need to apply a force larger than gravity. Think about that the next time you jump into the air. You are overcoming gravity for a brief second. Enjoy it while it lasts. Eventually, gravity will win the battle.

Question: "How can humans overcome gravity?"

Response: "Jumping"

A: yes

What a time of it Dawson's Landing was having! All its life it had been asleep, but now it hardly got a chance for a nod, so swiftly did big events and crashing surprises come along in one another's wake: Friday morning, first glimpse of Real Nobility, also grand reception at Aunt Patsy Cooper's, also great robber raid; Friday evening, dramatic kicking of the heir of the chief citizen in presence of four hundred people; Saturday morning, emergence as practicing lawyer of the long-submerged Pudd'nhead Wilson; Saturday night, duel between chief citizen and titled stranger. The people took more pride in the duel than in all the other events put together, perhaps. It was a glory to their town to have such a thing happen there. In their eyes the principals had reached the summit of human honor. Everybody paid homage to their names; their praises were in all mouths. Even the duelists' subordinates came in for a handsome share of the public approbation: wherefore Pudd'nhead Wilson was suddenly become a man of consequence. When asked to run for the mayoralty Saturday night, he was risking defeat, but Sunday morning found him a made man and his success assured.

Question: "Who was asked run for the mayoralty Saturday night?"

Response: "Pudd'nhead Wilson"

A: yes

We need natural resources for just about everything we do. We need them for food and clothing, for building materials and energy. We even need them to have fun. Table 2.1 gives examples of how we use natural resources. Can you think of other ways we use natural resources? Use Vehicles Resources Rubber for tires from rubber trees Steel frames and other metal parts from minerals such as iron Example iron ore Electronics Plastic cases from petroleum prod- ucts Glass screens from minerals such as lead lead ore Use Homes Resources Nails from minerals such as iron Timber from trees Example spruce timber Jewelry Gemstones such as diamonds Minerals such as silver silver ore Food Sunlight, water, and soil Minerals such as phosphorus corn seeds in soil Clothing Wool from sheep Cotton from cotton plants cotton plants Recreation Water for boating and swimming Forests for hiking and camping pine forest Some natural resources are renewable. Others are not. It depends, in part, on how we use them.

Question: "What do we need for building material and energy"

Response: "Minerals"

A:
no