The best surface to run on is one that's
a. as hard as possible so that it adds more stability to your foot.
b. hilly so that you can improve your cardiovascular endurance.
c. smooth and soft so that it can cushion the stresses of running.
d. uneven so that the tendons and ligaments in the ankles and knees are strengthened.

Which of the following are energy solutions that release pollution into the air>

Match each description to the appropriate biome. tropical savanna desert tropical rain forest taiga tundra has sparse vegetation and very cold temperatures located near the equator and contains trees that form dense canopy layers is very hot and dry, and has plants that need little water has cold winters, heavy snowfall and is dominated by conifers has warm temperatures and is dominated by grasses

Select the correct answer from each drop-down menu proteins are