The Houston area has over 150 active faults (estimated to be 300 active faults) with an aggregate length of up to 310 miles (500 km), including the Long Point–Eureka Heights fault system which runs through the center of the city. There have been no significant historically recorded earthquakes in Houston, but researchers do not discount the possibility of such quakes having occurred in the deeper past, nor occurring in the future. Land in some areas southeast of Houston is sinking because water has been pumped out of the ground for many years. It may be associated with slip along the faults; however, the slippage is slow and not considered an earthquake, where stationary faults must slip suddenly enough to create seismic waves. These faults also tend to move at a smooth rate in what is termed "fault creep", which further reduces the risk of an earthquake.
How many estimated active faults does Houston have?
300

Indoor lighting is usually accomplished using light fixtures, and is a key part of interior design. Lighting can also be an intrinsic component of landscape projects.
What is considered a key part of interior design?
Indoor lighting

The controversy surrounding affirmative action's effectiveness is based on the idea of class inequality. Opponents of racial affirmative action argue that the program actually benefits middle- and upper-class African Americans and Hispanic Americans at the expense of lower-class European Americans and Asian Americans. This argument supports the idea of class-based affirmative action. America's poor is disproportionately made up of people of color, so class-based affirmative action would disproportionately help people of color. This would eliminate the need for race-based affirmative action as well as reducing any disproportionate benefits for middle- and upper-class people of color.
Which idea is the controversy of affirmative action primarily based upon?
class inequality