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:2
Explanation: Sperm cells in plants are found inside the pollen grain. When the pollen grains fall on the stigma, the pollen raptures and forms a pollen tube then the sperm cells pass through the pollen tube to the ovary.
I’m guessing San francisco was cooler and st. louis was warmer?
Answer:
hydrologic cycle
Explanation:
Water cycle. Water cycle, also called hydrologic cycle, cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many processes involved in the water cycle, the most important are evaporation, transpiration, condensation, precipitation, and runoff.
hope this helps :)
Answer:
Toxic Algae Blooms
Explanation:
Floodwater deposits a large amount of sediment. excess nutrients promote the growth of algae is a cause of eutrophication.
