Wo charged spheres are 1.5 m apart and are exerting an electrostatic force (fo) on each other. if the charge on each sphere decreases by a factor of 9, determine (in terms of fo) how much electrostatic force each sphere will exert on the other.

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.