QUES: On runways, green lights indicate the beginning of the runway for landing, while red lights indicate the end of the runway. Runway edge lighting consists of white lights spaced out on both sides of the runway, indicating the edge. Some airports have more complicated lighting on the runways including lights that run down the centerline of the runway and lights that help indicate the approach (an approach lighting system, or ALS). Low-traffic airports may use pilot controlled lighting to save electricity and staffing costs.

What may low-traffic airports use to save electricity and staffing costs?
What is the answer?
ANS: pilot controlled lighting
QUES: Because of their long life, fast switching times, and their ability to be seen in broad daylight due to their high output and focus, LEDs have been used in brake lights for cars' high-mounted brake lights, trucks, and buses, and in turn signals for some time, but many vehicles now use LEDs for their rear light clusters. The use in brakes improves safety, due to a great reduction in the time needed to light fully, or faster rise time, up to 0.5 second faster[citation needed] than an incandescent bulb. This gives drivers behind more time to react. In a dual intensity circuit (rear markers and brakes) if the LEDs are not pulsed at a fast enough frequency, they can create a phantom array, where ghost images of the LED will appear if the eyes quickly scan across the array. White LED headlamps are starting to be used. Using LEDs has styling advantages because LEDs can form much thinner lights than incandescent lamps with parabolic reflectors.

ED brake lights are how many times slower than incandescent ones?
What is the answer?
ANS: unanswerable
QUES: Norfolk Island Hospital is the only medical centre on the island. Medicare and the Pharmaceutical Benefits Scheme do not cover Norfolk Island. All visitors to Norfolk Island, including Australians, are recommended to purchase travel insurance. Although the hospital can perform minor surgery, serious medical conditions are not permitted to be treated on the island and patients are flown back to mainland Australia. Air charter transport can cost in the order of A$30,000. For serious emergencies, medical evacuations are provided by the Royal Australian Air Force. The island has one ambulance staffed by St John Ambulance Australia volunteers.

What are visitors of Norfolk Island recommended to sell?
What is the answer?
ANS:
unanswerable