The answer is A or the first one
Sound waves are both compressional and longitudinal, (although we frequently draw them as transverse waves).
Longitudinal waves are where the particles of matter collide into one another, pushing them into the next and then oscillating back. This is how sound travels. This is also why sound can only travel through a medium, it cannot travel through a vacuum, as is shown here:
A gene pool changes throughout evolution this could be natural selection, genetic drift or a mutation. A gene pool does this to adapt with the needs of the environment it is in
Answer:
C. About 18 percent of the variation in blood pressure can be explained by a linear relationship between blood pressure and caffeine consumed.
Explanation:
Here, r = 0.428
∴ We can say it will give a positive curve, as 0.428 indicates it is a positive correlation.
Though the amount of correlation is low, still it is positive and more than 0.4
So, nearly about 18% of the variation in the blood pressure can be observed by the consumption of caffeine water. As consumption of caffeine water and blood pressure is both increasing so we can say that r= 0.428 will give a positive linear curve.