Polar front jet stream Summer (60 km/h)
Polar front jet stream - Winter
For the eastern United States, the change the polar
front jet stream from this summer position to this winter
position caures
(1) warmer temperatures farther north and causes
storms to move more slowly
(2) warmer temperatures farther north and causes
storms to move more rapidly
(3) cooler temperatures farther south and causes
storms to move more slowly
(4) cooler temperatures farther south and causes
storms to move more rapidly.
United States
(125 km

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

What type of weather does tropical continental air bring in summer? hot and cloudy cool and sunny hot and sunny cool and cloudy

Gram-negative bacteria have a cell wall that is! and does not accept the stain, making itappear