A roller coaster ride begins with a chain and motor. The cart carrying the people is pulled by the chain, powered by the motor, to the top of a tall hill and then let loose to coast down. The cart then continues to follow the track until it reaches the end. Kinetic energy is dependent upon the mass of the object and the speed of the object. At which point of the ride is the kinetic energy the greatest?

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The images show two species of tree frogs in a particular region. the gray tree frogs are adapted to the trees of the woodlands, while the green tree frogs can survive in woodlands or grasslands. the gray frog was abundant in the woodlands. because of climatic changes, most of the trees in the region died, and the woodlands changed to grasslands. in such a case, the . the gray tree frog is closely related to the green tree frog genetically, but they have different mating calls. this suggests that speciation occurred because of .