Select all the correct answers.
giraffes with short necks lived in arid regions and fed on grasses. over time, grasses disappeared, forcing giraffes to eat from trees. mutations in
the genome led to some giraffes inheriting the trait for long necks. over time, there were more giraffes with long necks in the region. what are
the two reasons for the change in the population of giraffes?
adaptation
o
artificial selection
natural selection
analogous structures

Describe different biomes. what are some adaptations that organisms (plants or animals) must have to live in each biome?

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

Click the game tab at the bottom of the simulation and select level 1. (there is no seesaw balance for this part of the activity.) balance the first equation, and click check to see if you got it right. if you can’t balance it in the first try, you can try again. work through the five equations for level 1. click continue to go on to level 2, and later level 3. each level is more difficult than the one before. keep trying until all the equations are balanced. in one or two sentences, describe how you did in the balancing game. in a few more sentences, explain one strategy you learned for balancing more complex equations.