Amajor process by which the sun's energy is transported around the earth system?

The diagram shows a boulder rolling down a hill into a valley and then up the opposite hill. at which position does the boulder have the greatest kinetic energy? ab c d

What is the period of a wave traveling 5 m/s if its wavelength is 20 m/s

According to piaget’s stages of cognitive development, the child does not differentiate between self and other objects. the child repeats rewarding activities, discovers new ways to get what he or she wants, and may have imaginary friends. which period is described?