Answer: air mass
Explanation: An air mass is a large body of air with generally uniform temperature and humidity. The area over which an air mass originates is what provides its characteristics. As such, air masses are associated with high pressure systems.
Answer:
Natural selection is an important contribution to the theory of evolution because it increases an individual's ability to survive and compete and reproduce.
Explanation:
They have increased need to carbohydrates, protein, water and iron.
Carbohydrates is the primary source for energy and active people apparently need more energy for their daily activities.
Protein helps build muscles, even though they only need a small amount more of protein than normal people, they still require protein for muscle buildings.
Water has to be needed as they may excrete more sweat by active activities in the day time. Water can also help remove waster material from body.
Iron helps the production of hemoglobin, which is in the red blood cells that help transport oxygen. As they exercise more, they need more oxygen supply for respiration, therefore there is a need for iron supply.
B. Forces can act on object and cause motion .....
the forelimb help with balance and crawling and the hind limbs are stroger than the forelimbs and they are used for jumping/hopping
