Q: What are electromagnetic waves with the longest wavelengths called? Read this paragraph and choose the correct option from the provided answers: Electromagnetic waves on the left side of the Figure above are called radio waves. Radio waves are electromagnetic waves with the longest wavelengths. They may have wavelengths longer than a soccer field. They are also the electromagnetic waves with the lowest frequencies. With their low frequencies, they have the least energy of all electromagnetic waves. Nonetheless, radio waves are very useful. They are used for radio and television broadcasts and many other purposes. You can learn more about radio waves, including how they were discovered, at this URL: http://www. youtube. com/watch?v=al7sFP4C2TY . Choices: - channel waves - sound waves - infrared waves - radio waves A:
radio waves
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Q: The epidermis consists mainly of what type of cells? Read this paragraph and choose the correct option from the provided answers: Cell Layers of the Epidermis. The epidermis consists mainly of epithelial cells. Choices: - cytoplasm - blood cells - crystalline - epithelial A:
epithelial
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Q: Does overhead irrigation or drip irrigation use less water? Read this paragraph and choose the correct option from the provided answers: Irrigation is the single biggest use of water. Overhead irrigation wastes a lot of water. Drip irrigation wastes a lot less. Figure below shows a drip irrigation system. Water pipes run over the surface of the ground. Tiny holes in the pipes are placed close to each plant. Water slowly drips out of the holes and soaks into the soil around the plants. Very little of the water evaporates or runs off the ground. Choices: - mist irrigation - stream irrigation - constant flow - drip irrigation A:
drip irrigation
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Q: Which reaction between alkyl halides and ammonia makes alkylamines? Read this paragraph and choose the correct option from the provided answers: molecular masses. Primary amines tend to have boiling points intermediate between those of the corresponding alcohol and alkane. Moreover, secondary and tertiary amines have lower boiling points than primary amines of comparable molecular mass. Tertiary amines form cations analogous to the ammonium ion (NH 4+), in which all four H atoms are replaced by alkyl groups. Such substances, calledquaternary ammonium salts, can be chiral if all four substituents are different. (Amines with three different substituents are also chiral because the lone pair of electrons represents a fourth substituent. ) Alkylamines can be prepared by nucleophilic substitution reactions of alkyl halides with ammonia or other amines: Equation 24.12. Choices: - nitrogen catabolism - conductive substitution reactions - nucleophobic reactions - nucleophilic substitution reactions A:
nucleophilic substitution reactions
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