Question

question 8
which situation best shows causation?
as a runners speed increases, the runners heart rate also increases.
as ice cream sales increase, the sale of sunscreen also increases.
when the number of train tickets sold increases, the kangaroo population also increases.
when the amount of daylight each day decreases, the number of christmas trees increases

Explanation:

Causation means one event causes another. When a runner's speed increases, their body needs more oxygen, so the heart rate increases as a direct result. In the other options, the relationships are likely due to other factors (e.g., ice - cream and sunscreen sales may both increase in summer, but one doesn't cause the other; train tickets and kangaroo population, and daylight and Christmas trees have no causal link).

Answer:

As a runner's speed increases, the runner's heart rate also increases.