The correct answer is "they allow traffic to proceed at the speed limit".
First of all, letter B is incorrect as the main function of the speed humps is not to bring harm to the motorists but to ensure the safety of the flow of the traffic. Letter A is correct as speed humps makes the motorists slow down on purpose for the traffic to proceed at a certain speed limit.
Answer:
Undergrowth of water plants hypoxia
Low levels of oxygen.
Explanation:
Eutrophication occur when lake or river has adequate nutrients that will encourage the growth of water plants i.e algae which lead to the depletion of dissolved oxygen in the lake. The growth of algae is increased due to availability of carbondioxide or phosphorus or nutrients required for photosynthesis. This result in tainted drinking water,hypoxia and degradation of recreational activities.
Answer:
The correct answer is option B. pheromones.
Explanation:
Pheromones are chemical substances that are released and produced by a different type of animals, into the environment, for marking their territory or affecting behaving of its species.
Wolves communicate by the chemical messages using their sense of smell. Such chemical messages are called pheromones, between different members of the same species.
Thus, the correct answer is option B. pheromones.
The answers are principles C and D. After the big bang, particles in gas clouds were closer to each other and clumped up faster. As they clumped together, they gained more gravitational force, eventually creating asteroids, stars, and planets.
