Two cannons sit on top of a 100 m high cliff. they fire identical cannon balls at the exact same moment. cannon ball a is fired at 20 m/s. cannon ball b is fired at 15 m/s. what will cannon ball b's vertical velocity (vx) be after 3 seconds?

Hydroelectricity provides about 7 percent of the electricity generated in the united states. (a) explain how a hydroelectric power plant converts energy stored in water into electricity. (b) identify two factors that determine the amount of electricity that can be generated by an individual hydroelectricity power plant. (c) describe the two main types of land-based hydroelectric power plants. (d) describe two economic advantages and two environmental disadvantages of hydroelectricity.