The outdoor lighting may not be turning on automatically anymore due to a malfunction in the timer or sensor that controls the automatic function. It could also be caused by a power outage or a tripped circuit breaker disrupting the electrical supply to the lights. Additionally, there may be an issue with the wiring or connections that is preventing the automatic activation of the lights. It is recommended to check these components and troubleshoot the system to determine the exact cause of the problem. **

There could be several reasons why the outdoor unit of the air conditioner is not turning on. It could be due to a tripped circuit breaker or a blown fuse, which would prevent power from reaching the unit. Another possibility is a malfunctioning thermostat or a problem with the wiring. Additionally, the unit may be experiencing a mechanical or electrical issue that requires professional repair. It's important to troubleshoot the problem carefully and, if necessary, seek the assistance of a qualified HVAC technician to diagnose and fix the issue. **

To prevent gold-colored fashion jewelry from turning black, it is important to properly care for and store the jewelry. Avoid exposing the jewelry to harsh chemicals, such as perfumes, lotions, and hairsprays, as these can cause the gold plating to tarnish. Additionally, remove the jewelry before swimming or showering to prevent exposure to chlorine and other chemicals. Store the jewelry in a dry, airtight container or jewelry box to prevent oxidation. Regularly clean the jewelry with a soft cloth to remove any oils or dirt that can contribute to tarnishing. **

Longitudinal turning involves cutting along the length of the workpiece, while face turning involves cutting across the face of the workpiece. Longitudinal turning is used to create cylindrical shapes and grooves, while face turning is used to create flat surfaces and contours. Additionally, longitudinal turning is typically used for creating external features, while face turning is used for creating internal features. **

Face turning and longitudinal turning are two different types of machining operations used in metalworking. Face turning involves cutting material from the surface of a workpiece to create a flat surface, while longitudinal turning involves cutting material from the length of the workpiece to create a cylindrical shape. In face turning, the cutting tool moves perpendicular to the workpiece, while in longitudinal turning, the cutting tool moves parallel to the workpiece. Overall, the main difference between the two is the direction in which the cutting tool moves in relation to the workpiece. **

A turning point with a horizontal turning tangent occurs when the slope of the curve at that point is zero, meaning the tangent line is horizontal. This indicates that the function changes from increasing to decreasing or vice versa at that point. In other words, the function reaches a maximum or minimum value at that point. This type of turning point is also known as a stationary point. **

Turning off refers to the action of deactivating or shutting down a device, system, or appliance. This typically involves stopping the flow of power or energy to the device, causing it to cease functioning. On the other hand, turning on refers to the action of activating or starting a device, system, or appliance. This involves initiating the flow of power or energy to the device, allowing it to begin functioning. In essence, turning off stops the operation of something, while turning on initiates its operation. **

It is unclear what "that" refers to in the question. If "that" refers to a specific object or device, please provide more context so that I can accurately answer the question. **