You would expect an earthworm to have no exoskeleton because as you see it is very flexible and soft. Organisms with such have body parts that are divided and an earthworm do not have any visible parts on them also having an exoskeleton would not allow an organism to move like an earthworm does.
Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
<span>I believe the answer would be B - the toy car would hit another toy car that would in turn hit another toy car, and so on. A wave has a ripple effect, so it will continue to happen down the line, until there is a force that stops it, or there are no more cars to hit.</span>
False because many different species are going extinct within our lifetime