Fig(a):Before winter Fig(b):During winter (c):After winter Robert was doing a study on bears , he observed a bear for a year and noticed the above changes. Can you help Robert to understand the changes and the reason behind it?

A1200 kg car traveling north at 10 m/s is rear-ended by a 2000 kg truck traveling at 30 m/s. what is the total momentum before and after the collision?

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i. e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.