Like you might have studied. Heated hair expands while colder air contracts. So, the sound isn't able to move as efficiently in cold air than it would in warmer air.
Question is which is NOT a good technique.
Answer is "B" and here's why:
A) Clear questions -- good. People understanding the question will answer accurately.
C) Large sample size -- good. Answers will be more accurate with more people asked (like if you flip a coin 1,000 times its going to be closer to 50% heads than if you only flipped it twice)
D) Random sample -- good. Avoids your own bias in choosing who to ask.
B) Push poll -- bad. Pretends to be unbiased, the pollster's real objective is to get a person thinking in a way that is to their advantage. Some political candidates do this just before elections.
Answer: A (physical property)
Explanation:
It says they both had clear liquids in each cup and since ice floats on water the only option that makes sense is A. There were no chemical, magnetic, or temperature tests made.
Answer:
permeability
Explanation:
dictionary definition: the state/quality of a material or membrane that causes it to allow liquids or gases to pass through it
in biology we use this term to describe the cell membrane, it is "semi-permeable" because it allows certain gasses and molecules to pass through
