What cause is Bryan comparing to ""the cause of liberty"" and ""the cause of humanity""? the gold standard free silver Populism

Earth's atmosphere is unique among the planets and is able to support life because it contains a large amount of a) oxygen b) helium c) methane d) carbon dioxide

These two squirrels live in the same ecosystem. what type of interaction do the images represent? a. direct competition b. mutualism c. interference competition d. symbiotic e. indirect competition

What are the three stages of volcanic activity? a. active, magma, lava c. extinct, eruption, explosive b. eruption, quiet, explosive d. active, dormant, extinct