Answer:
Labor unions give workers the power to negotiate for more favorable working conditions and other benefits through collective bargaining. Union members earn better wages and benefits than workers who aren't union members. On average, union workers' wages are 28 percent higher than their nonunion counterparts.
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 Mayan and other Mesoamerican cultures used a vigesimal number system based on base 20 (and, to some extent, base 5), probably originally developed from counting on fingers and toes. The numerals consisted of only three symbols: zero, represented as a shell shape; one, a dot; and five, a bar.
