The reason why a person walking would havea higher heart rate than a person running would be because if the person who is walking is not used to walking, this could tax his body more, relatively to the person who is running and is actually more physically active and for that reason his run is not taxing his body as much. The better grave deserves the person who is running.
YaYAYAYAYYAAYAYAYAYAYAYYA
In other words, Yes.
I would say the answer is C. D isn't right because mammoths didn't exist when dinosaurs did. And cyanobacteria were the first living organisms on earth.
