Why do areas north of the arctic circle in the northern hemisphere experience a polar day lasting for several months during summer?

Why do german shepherds shed so much

During endocytosis, cells expel what they don't need take in what they need shrink due to loss of water

Select the situation bellow that would produce a total displacement of zero. a. a trip to the moon and then to mars b. a horse galloping from one end of a field to another c. the criss-crossing path of a bug as it flies from flower to flower d.a round-trip ride to school and back