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.
The orca, or killer whale, for example, is actually the largest member of the dolphin family. Dolphins are by far more prevalent than porpoises. Most scientists agree that there are 32 dolphin species (plus five closely related species of river dolphin) and only six porpoise species.
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Regulation of opening and closing of stomata
Answer:
Protozoology should be the answer.
Hii and says he will not have any other plans to because he’s going up to north and north west of west