Answer the following question given this paragraph: Nuclear fission is the splitting of the nucleus of an atom into two smaller nuclei. This type of reaction releases a great deal of energy from a very small amount of matter. It begins when the nucleus of a radioactive atom gains a neutron. Q: What term describes the splitting of the nucleus of an atom into two smaller nuclei? Choices: - nuclean fusion - atomic reaction - critical fission - nuclear fission A:
nuclear fission
Answer the following question given this paragraph: Sometimes two different minerals have the same chemical composition. But they are different minerals because they have different crystal structures. Diamonds are beautiful gemstones because they are very pretty and very hard. Graphite is the "lead" in pencils. It's not hard at all! Amazingly, both are made just of carbon. Compare the diamond with the pencil lead in Figure below . Why are they so different? The carbon atoms in graphite bond to form layers. The bonds between each layer are weak. The carbon sheets can just slip past each other. The carbon atoms in diamonds bond together in all three directions. This strong network makes diamonds very hard. Q: Graphite and diamond both are made from carbon. what makes diamonds so hard? Choices: - weak atomic network - strong metallic network - strong light network - strong atomic network A:
strong atomic network
Q: Answer the following question given this paragraph: Particles with opposite electric charges attract each other. This explains why negative electrons orbit the positive nucleus. Particles with the same electric charge repel each other. This means that the positive protons in the nucleus push apart from one another. So why doesn't the nucleus fly apart? An even stronger forcecalled the strong nuclear forceholds protons and neutrons together in the nucleus. You can learn more about these forces in the nucleus by watching the video at this URL:. Q: Particles with what type of electric charges attract each other? Choices: - similar - same - simple - opposite A:
A: opposite
Question: Answer the following question given this paragraph: This tiny plant can use the energy of the sun to make its own food. You can't make food by just sitting in the sun. Plants are not the only organisms that can get energy from the sun, however. Some protists, such as algae, and some bacteria can also use the energy of the sun to make their own food. Q: What is the main type of organism that gets its energy directly from the sun? Choices: - animals - carnivores - consumers - plants A:
Answer: plants
*Question*
Answer the following question given this paragraph: Lightning is the discharge of static electricity that has built up on clouds. Every year, the earth experiences an average of 25 million lightning strikes. Lightning bolts travel at speeds up to 60,000 miles per second, and can reach temperatures of 50,000F, which is five times the temperature of the surface of the sun. The energy contained in a single lightning strike could light a 100 Watt light bulb 24 hours per day for 90 days. Q: Where do lightnings build up? Choices: - stratosphere - air - troposphere - clouds A:
**Answer**
clouds
(Q).
Answer the following question given this paragraph: Recall that our DNA is wound into chromosomes . Each of our chromosomes contains a long chain of DNA that encodes hundreds, if not thousands, of genes. Each of these genes can have slightly different versions from individual to individual. These variants of genes are called alleles . Each parent only donates one allele for each gene to an offspring. Q: What are variants of genes called? Choices: - antigens - mutations - allergens - alleles A:
(A).
alleles