You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).

[EX Q]: Paragraph: Warm air is less dense than cool air, so it rises higher in the troposphere.
 Question: If Jim raises the temperature of the air inside his balloon, will his balloon rise higher into the air or sink towards the ground? 
 Choices: A)rise higher 
B)sink lower
[EX A]: rise higher

[EX Q]: Paragraph: For a given medium such as air, sound has a slower speed at lower temperatures.
 Question: If Mary is blowing an air horn underwater and she lowers the temperature of the water, what will happen to the speed of the sound waves generated by the air horn? 
 Choices: A)increase 
B)decrease
[EX A]: decrease

[EX Q]: Paragraph: Higher frequency waves have greater energy.
 Question: Waves that come in very fast to the shores have 
 Choices: A)more energy 
B)less energy
[EX A]:
more energy