Two airplanes leave an airport at the same time. the velocity of the first airplane is 740 m/h at a heading of 26.1 ◦ . the velocity of the second is 640 m/h at a heading of 109◦ . how far apart are they after 1.8 h?

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.