After soccer practice, Coach Miller goes to the roof of the school to retrieve the errant soccer balls. The height of the school is 3.5 m 3.5 m. He kicks a soccer ball which leaves the roof with a horizontal velocity, but no vertical velocity. Ignoring air resistance, which of the following values indicates how much horizontal velocity is needed for the ball to reach the soccer field located 22 m 22 m from the school?

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.