Here is a question about this article: The first blue-violet LED using magnesium-doped gallium nitride was made at Stanford University in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories, where he collaborated with Jacques Pankove on related work. In 1971, the year after Maruska left for Stanford, his RCA colleagues Pankove and Ed Miller demonstrated the first blue electroluminescence from zinc-doped gallium nitride, though the subsequent device Pankove and Miller built, the first actual gallium nitride light-emitting diode, emitted green light. In 1974 the U.S. Patent Office awarded Maruska, Rhines and Stanford professor David Stevenson a patent for their work in 1972 (U.S. Patent US3819974 A) and today magnesium-doping of gallium nitride continues to be the basis for all commercial blue LEDs and laser diodes. These devices built in the early 1970s had too little light output to be of practical use and research into gallium nitride devices slowed. In August 1989, Cree introduced the first commercially available blue LED based on the indirect bandgap semiconductor, silicon carbide (SiC). SiC LEDs had very low efficiency, no more than about 0.03%, but did emit in the blue portion of the visible light spectrum.[citation needed]
What is the answer to this question: When was the first blue-violet LED developed?
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So... 1972


Here is a question about this article: The nation's military relies heavily on high-tech weapons systems designed and manufactured in Israel as well as some foreign imports. The Arrow missile is one of the world's few operational anti-ballistic missile systems. The Python air-to-air missile series is often considered one of the most crucial weapons in its military history. Israel's Spike missile is one of the most widely exported ATGMs in the world. Israel's Iron Dome anti-missile air defense system gained worldwide acclaim after intercepting hundreds of Qassam, 122 mm Grad and Fajr-5 artillery rockets fire by Palestinian militants from the Gaza Strip. Since the Yom Kippur War, Israel has developed a network of reconnaissance satellites. The success of the Ofeq program has made Israel one of seven countries capable of launching such satellites.
What is the answer to this question: The military relies on what?
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So... high-tech weapons systems


Here is a question about this article: The latest study using magnetic resonance imaging (MRI) to humans and dogs together proved that dogs have same response to voices and use the same parts of the brain as humans to do so. This gives dogs the ability to recognize emotional human sounds, making them friendly social pets to humans.
What is the answer to this question: What technology was used to show that dogs respond to voices in the same brain parts as people?
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So...
MRI