Extention to Europe
I think
The answer is steamboats! The first steamboat came year 1807 and was invented by John Fitch:)
Answer:
B. All of these are drivers
Explanation:
The populations of lot of amphibians, with rare exceptions, are constantly on the decline around the world. The main reason behind this is the human activity, as it has caused lot of changes, pollution, and dangers for the amphibian populations, which has led lot of amphibians to be on the verge of extinction.
The pollution, especially of the waters, has been a major factor for the decline of the amphibian population. Lot of very toxic chemicals have made the water unsuitable for living and poisonous, which systematically killed off the amphibian populations.
The habitat loss, as with any other group of animals, has left the amphibians without places to live. They have been left without their shelters, food sources, mating grounds, and they have started to die out.
The invasive species, especially the predatory ones, have also had big negative impact. The amphibians didn't had any defense mechanism against the introduced predators, so they were easy prey and their numbers rapidly went down.
The speed of a wave measures how far one particular crest (or trough) moves in a given amount of time. The speed of the wave changes according to the following equation:
v = λ
* f
According this equation, it follows that as the speed and length of a wave decreases, the wave grows higher (the higher the frequency).
Because the earth is tilted on a axis and tilts differently to get the 4 different seasons