The tundra ecosystem of Alaska is known as a “cold desert.” It receives very little precipitation, about four inches annually. However, it is rich in wetlands due to permafrost, which traps moisture close to the surface. The temperatures vary widely, also producing persistent winds. Although treeless, the Arctic tundra is an abundant ecosystem. Many organisms find their niche here including many migratory bird species and mammals such as caribou, foxes, bears, and small rodents. Which factor of the tundra ecosystem is biotic?

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant

Researchers determine that the biodiversity in a woodland region is declining. they identify two major threats to the region's biodiversity, a method to address each threat, and the expected outcome of each method. this information is shown in the table. a) reforestation would not benefit many species because most forest species live on the ground. b) reforestation would take the longest time to be effective because trees take several years to grow. c) biological augmentation would benefit only a few species because is is typically not very effective. d) biological augmentation would take less time to ve effective because it targets the majority of prey species.

Aparticle moves in the xy plane with constant acceleration. at time zero, the particle is at x = 6 m, y = 8.5 m, and has velocity ~vo = (9 m/s) ˆı + (−2.5 m/s) ˆ . the acceleration is given by ~a = (4.5 m/s 2 ) ˆı + (3 m/s 2 ) ˆ . what is the x component of velocity after 3.5 s? answer in units of m/s.