Read the excerpt from A Black Hole Is NOT a Hole by Carolyn Cinami DeCristofano. Einstein's idea of gravity had big consequences. It helped explain some observations that Newton's idea didn't account for. It also opened our minds to amazing new possibilities. For example, taking his cue from Einstein's idea that space bends, scientist Karl Schwarzschild began to think about what would happen if a place in space were extremely distorted. His light would follow the hyper-bent space, never to turn away from it. This was the first prediction of a black hole. At first, some scientists (including Einstein!) rejected Schwarzschild's ideas. Others were intrigued and began searching the skies for real black holes. Just decades later, they found the first of them. It just goes to show: sometimes, as Einstein himself once said, "Imagination is more important than knowledge."

3one of the biggest impacts a building has on earth is the energy it uses. currently, most of the world’s energy comes from burning fossil fuels. these fuels are dirty and when they are burned they pollute the air and water. one way to burn fewer fossil fuels is to reduce the amount of electricity a building has to use. passive solar heating, which uses heat from the sun, reduces the amount of fossil fuel used to heat buildings. passive solar heating requires a south-facing wall made of glass. when sunlight shines through the wall, it is collected and used to warm the building. another way green buildings reduce their electricity use is to install other energy sources. for example, some green buildings use panels that turn energy from the sun into useable electricity. which is the best summary of paragraph 3? a) fossil fuels are dirty and pollute the air and water. most of the world's energy comes from these fuels. b) the biggest problem of buildings is that they use fuel that is dirty for heating. they need to do something to be more energy efficient. c) panels that turn energy from the sun into electricity and passive solar heating can stop the burning of fossil fuels which pollute air and water. d) since fossil fuels are dirty and pollute the air and water, other technologies that pollute less and produce energy have been developed like solar energy and green buildings.