Answer:
Unbalanced
Explanation:
The forces acting upon Colin, his friends pushing and gravity, are unbalanced
<span>Animals pass down their features to their children when they breed. </span>When you separate a population (or group of animals of the same species), say by building a large wall, they can't interbreed with each other. This means that if an animal on one side of the border gets an adaptation, it won't pass it on to the other animal. Soon, each side will evolve different adaptations, and the two populations will become so different that they become two different species.
It is possible that one-half wouldn't be able to survive, and go extinct, but it doesn't happen all the time (A is incorrect). Similarly, the populations don't ALWAYS evolve into two different species, though they may (B is incorrect). However, if the environments differ enough, they will acquire different adaptations through evolution. C is correct! Keep in mind that D is incorrect: the first part, the populations can't interbreed, is correct, but that doesn't mean they will die off.
Answer: C
Answer
Frequency of stimulus can change the force of muscle twitch.
Explanation
Twitch is tension produced by the contraction of a small muscle or it is muscle fasciculation. Its strength depends on the stimulation frequency. If the frequency is higher then temporal summation takes place and produce higher tension in the muscle. If the frequency is weak then less tension is produced in the muscle. This force also depends on the cross-sectional area of muscle.
A classification system is a system with a distribution of classes created according to common relations.
