Answer: D. Hypothesis B is more useful because it suggests a way to test the relationship between heart rate and caffeine intake.
Hypothesis A and B both are suggesting that caffeine intake is related to higher heart rate. But hypothesis B is proving it more certainly by suggesting the affects of caffeine intake on heart rate. As, heart rate of most people will be higher 30 minutes after they drink a cup of coffee is testifying the fact, that higher heart rate is related with caffeine intake.
Therefore, hypothesis B is more useful because it suggests a way to test the relationship between heart rate and caffeine intake.
Answer:
C. It uses a renewable resources
Answer:
This is because there is no air in space – it is a vacuum. Sound waves cannot travel through a vacuum. ... Even the emptiest parts of space contain at least a few hundred atoms or molecules per cubic metre. Space is also filled with many forms of radiation that are dangerous to astronauts.
Answer:
I believe there are 6
Explanation:
Protons are the positively charged circles (blue)
Neutrons are the Neutral (red)
and the others (green) are called electrons
