Which of the following is NOT a nitrogenous base?
adenine
thymine
guanine
alanine

World class speed skaters can skate a 3,000-m course in about 4 minutes. what is their average speed for this course. a. 12.5m/s b. 1.33m/s c. 13.3m/s d. 1.25m/s

When a population split into two subgroups what is most likely to cause the subgroups to develop different traits?

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping